Project Spartan and the Windows 10 January Preview Build

Yesterday, we announced that Windows 10 will ship with a brand new browser, codenamed “Project Spartan.” Designed for Windows 10, Spartan provides a more interoperable, reliable, and discoverable experience with advanced features including the ability to annotate on web pages, a distraction-free reading experience, and integration of Cortana for finding and doing things online faster.

Project Spartan on Windows 10 desktop

Spartan is a single browser designed to work great across the entire Windows 10 device family – from keyboard and mouse on the Windows 10 desktop to touch, gestures, voice, controllers and sensors.

Project Spartan on Windows 10 phone with dark theme     Project Spartan on Windows 10 phone with light theme

Powered by a new rendering engine, Spartan is designed for interoperability with the modern web. We’ve deliberately moved away from the versioned document modes historically used in Internet Explorer, and now use the same markup as other modern browsers. Spartan’s new rendering engine is designed to work with the way the web is written today.

Like Windows 10 itself Spartan will remain up-to-date: as a service, both providing new platform capabilities, security and performance improvements, and ensuring web developers a consistent platform across Windows 10 devices. Spartan and the new rendering engine are truly evergreen.

Spartan provides compatibility with the millions of existing enterprise web sites designed for Internet Explorer. To achieve this, Spartan loads the IE11 engine for legacy enterprise web sites when needed, while using the new rendering engine for modern web sites. This approach provides both a strong compatibility guarantee for legacy enterprise web sites and a forward looking interoperable web standards promise.

We recognize some enterprises have legacy web sites that use older technologies designed only for Internet Explorer, such as custom ActiveX controls and Browser Helper Objects. For these users, Internet Explorer will also be available on Windows 10. Internet Explorer will use the same dual rendering engines as Spartan, ensuring web developers can consistently target the latest web standards.

Dual rendering engine architecture animation

What does this mean to web developers?

If you are building a public consumer-facing web site here’s what you need to know:

  1. Our new rendering engine will be the default engine for Windows 10, Spartan, and Internet Explorer. This engine has interoperability at its core and consumes the same markup you send other modern browsers. Our standards support and roadmap can be found at
  2. Public Internet web sites will be rendered using the new engine and modern standards, and legacy Internet Explorer behaviors including document modes are not supported in the new engine. If your web sites depends on legacy Internet Explorer behaviors we encourage you to update to modern standards.
  3. Our goal is interoperability with the modern web and we need your help! You can test the new engine via the Windows Insider Program or using Please let us know (via Connect or Twitter) when you find interoperability problems so we can work with the W3C and other browser manufacturers to ensure great interoperability.

New features and fixes in the January Insider Update

On Friday, we’re also rolling out a new preview build to Windows 10 Insiders. This new preview will also be available on RemoteIE soon. This build doesn’t have Project Spartan yet, but does have lots of updates to the new web rendering engine that Spartan will use. We started testing our new rendering engine by rolling it out to a portion of Insiders using the Windows Technical Preview in November.

Since that time, we’ve received over 12,000 feedback reports through the smiley face icon alone. This new build has over 2000 changes to the new platform, largely influenced by that feedback. In addition to many fixes, there are also several new platform features we are thrilled to be releasing in the updated preview:

Additionally, you’ll find updated F12 developer tools that include the updated UI we shipped to IE11 users last month as well as several new features and improvements. Here’s a few of our favorites:

  • New and Improved Network Tool—capture and debug network traffic with new UX and capabilities, such as auto-start, a content type filter, and error highlighting.
  • HTML & CSS Pretty Printing—just as you’ve been able to nicely reformat minified JavaScript in the debugger, you’ll now be able to do this for HTML and CSS.
  • Async Callstacks for Events and Timers—quickly view the “async callstack” to connect the dots between event dispatch and the original addEventListener call or between setting a timer and the timer being fired.
  • Sourcemaps for Styles and in the Memory Profiler—jump to your original sources, such as TypeScript or SASS, directly from the Styles pane or Memory Profiler tools.
  • Find Reference and Go To Definition—jump directly to a function call’s definition or find the references to a given variable.

New F12 network tools

With these improvements, we’re increasing the number of Insiders that get the new engine as we work towards this as the default for all users. If you’re curious and want to opt-in now, remember to navigate to about:flags and set “Enable Experimental Web Platform Features” to Enabled.

We’re excited to share our continued progress with you and to introduce Project Spartan to the Microsoft family. Please continue to share your feedback via Twitter, UserVoice (feature requests) and Connect (bug reports) and help shape our next browser. We’ll also be holding our next Twitter #AskIE session on Tuesday, January 27th from 10AM-12PM PST so you can ask questions to the team. See you there!

— Jason Weber, Group Program Manager, Internet Explorer

Comments (148)

  1. Björn says:

    Congrats guys, this is looking like a amazing release!

  2. Daniel Schmidt says:

    May I ask what the new Browser UI is rendered in? Is it Win32 GDI, WPF, WinRT XAML, HTML/CSS, D2D custom rendering, DirectUI….

    I am really looking forward to trying it out for myself!



  3. Does the new Network tool export to standard formats (e.g. JSON-based HTTP Archive format – HAR) or popular ones (Session Archive Zip)?

    Does the new Network tool offer network emulation (e.g. bandwidth limits, latency simulation, etc)?

    Can you share details about your privacy choices for HSTS:…/https-everything-in-2015-with-free-certificates-and-hsts.aspx

    Any statement on the removal of P3P Support?

    Any news on whether Tracking Protection Lists will be supported?

    Will the old MJPEG streaming format (supported by other browsers, used by some webcams) be supported too?

    Will the Spartan effort include new web services (e.g. view my favorites list somewhere on OneDrive or whatnot)?

    Will there be new Fish-themed demos?

    When will Spartan be declared the final name and not just a code-name? Do we need to keep our lighters lit, or will we get this encore even if we don't?

    Will IE8's HTML5 implementation bugs around localStorage and postMessage be fixed?

    Can Desktop application developers using the WebOC today use the Spartan engine?

    Will Spartan run in Enhanced Protected Mode by default?

  4. GoodThings2Life says:

    I'm most curious to know if Spartan will support Group Policy templates for IT administrators (beyond Enterprise Mode lists and existing IE templates).

    After that, I'd like to know more about extensions/plugins and also the UserAgent string of Spartan.

  5. GoodThings2Life says:

    @EricLaw, I kinda hope they keep the Spartan name. Between HoloLens and Cortana and Spartan, it's good to see Microsoft learn how to name things. 😉

  6. Ryan Hayes says:

    ^ Yep, totally agree that they should keep the Spartan name as the final one.  Make it so!

  7. Andy Booth (Clusta) says:

    Shame on mobile there are both bars at the top (address bar) and bottom (app bar with commands). The clean simplicity of IE on WP 8.1 was great.

  8. MamaJama says:

    Where's the Mac version?

  9. Web Application Developers Everywhere says:

    Please stop developing browsers and concentrate on phasing out IE.  Take a page out of Netscape's book and stop development.  You lost and it's time to face that fact.  I'm not trying to be rude or sarcastic.  Please consider this approach.


    Web Application Developers Everywhere

  10. Domenic Denicola says:

    Will the async call stack support also work for promises?

  11. D Fowler says:

    Just wondering if you all were ready to discuss the web app/extension model? Will WinJS be part of it and what is the story for developers making extensions and add ons for FireFox and Chrome?

  12. Fred says:

    @Web Application Developers Everywhere

    Any sentence that starts with "I'm not trying to be rude…".

    You don't even know anything about the new browser, what qualifies you to comment on this at all?

  13. Brian LePore says:

    This article really didn't help clear up anything for me.

    Both browsers will include both rendering engines and will default to the modern engine. So what makes them different exactly?  Is the difference only that IE loads ActiveX controls and Browser Helper Objects while Spartan does not? And how does it determine when to change between the modes? Can the mode switch depending on the page or is it on the whole site?

    What makes the new version different from the old other than it will support auto-updating to add new features? Beyond that it sounds like a typical new IE release with new features being added and the ability to fall back to older modes if that is necessary.

  14. Leo Koester says:

    WTF is that address bar doing up there?? All that wasted space with all that buttons and stuff??

    Please, PLEASE do not destroy this awesome interface that Internet Explorer has today at Windows Phone 8.*.

  15. Jeffrey Gilbert says:

    All of these questions and more answered at

    EXCEPT, when can we expect a VM image with spartan on it on so we can give the browser a trial run and provide proper feedback?

    Also, can we really not step away from the past yet? MSFT have labeled IE 5.5 EOL for ages, even having broken from tradition with IE11 by rendering in standards mode and turning off non-standard javascript APIs in it by default. Why would MSIE need to support an IE11 rendering engine which should behave the same as Spartan, a project which presumably has the same or better standards support, unless… wait, is this browser just IE5.2 for the mac wrapped in a new shell? TRICKY TRICKY!

  16. Why says:

    This looks like chrome.  Please contribute to chrome if you want to make the web browser better.   All this does is increase development costs by having to support another browser.  Enough damage has been done by IE.  Please stop development.

  17. Josh says:

    @ Web Application Developers Everywhere

    If you're going to ask them to do a Netscape, they actually are. Because born out of the ashes of Netscape was Firefox, which ran on a fork of Netscape's layout engine. It is the same with IE and Spartan. It would be very dangerous for the Open Web if Microsoft decided to just use Blink or WebKit.

  18. Vitor Canova says:

    Totally agree to keep the name Spartan. Probably you already own it.

    But regard the Spartan visual I'm missing the transparent chrome over there.

    In the mobile version I think you are stolen too much space. The actual version is just a minimum bar in the bottom. You are using the top AND the bottom now. Please at least make the bottom just "…". But I really like the way it is now.

  19. Sardoc says:

    So… this basically means Spartan will be available only for Win 10? I really hope not. That would just be dumb, literally giving away market share to… ugh… Chrome. The older OSes (especially Vista/2008) could well use a newer browser, and I'm sure Win 7/2008R2 users probably wouldn't mind one, either.

  20. Joe says:

    I really wish the phone version would have true tabs.  The way they are in WP8.1 (and appear to be in Spartan) has them hidden behind a menu, making them far more akin to the separate windows that we used before tabbed browsing became common.  Something like how Metro IE handles tabs would be far better, even on a small screen.

    In fact, rip off as much of the Metro IE user interface as possible, because that appears to be far nicer for tablets and phones.

  21. Alfonso says:

    @ Why & Web Application Developers Everywhere

    No, sane developers don't want a single engine.

    People want different engines that pushes each other forward, make things in a standard way (not like Chrome) and allows to check if the problem is their code or a bug in the browser.

    MS, please keep up with all the recent work and don't forget to provide Spartan directly to Windows 7 & 8.1 because we all know that many people won't upgrade their OS

  22. @Sardoc: I suspect the hope is that everyone on Win7 will take advantage of the free upgrade to Windows 10. That may be … optimistic.

  23. Louis says:

    Looks great, however I'm missing full support for webcomponents. What about "Spartan"-apps?

  24. Jeffrey Gilbert says:

    @Josh, agree to a point. I think the danger is that the web becomes stagnant due to a virtual need to provide legacy on older versions of IE. MSFT is effectively trying to give people no rational reason not to upgrade to a newer browser, but the reality is older systems that haven't upgraded to the latest system are mostly from china or aged hardware which cannot upgrade to a newer version of windows. Aside from that, many (virtual) machines running IE5.5-8 are automated systems like bots.

  25. Stilgar says:


    1. What is the extension model

    2. What about plugins? Silverlight? Flash?

    3. Will web slices still work? I love and still use those.

    And I have to agree @Andy Booth the mobile version looks like a downgrade. Also I wish you keep the name Spartan.

  26. Mathias says:

    I think moving the address bar below the tabs instead of next to the tabs is a huge waste of space. Why would I need a text box that spans nearly the entire window just to be able to type something like ""? I used IE11 mainly because it was the only browser that does not waste space like that. Now Spartan will look just like a copy of all the other browsers.

  27. Garyk says:

    rss feeds didn't automatically update in the last release, will they work in the next release of windows 10?

  28. Neyah says:


    Based on your reasoning, Chromium should never have come about in the first place.  Other browsers already existed prior to Chromium being developed, and its development required people to support another browser.

    Would you similarly reject out of hand any other browser development work that is not Chromium, or do you reserve that for Microsoft?  Do you also go around to anyone developing versions of Linux other than your favorite one, telling them to not bother?

  29. @Sardoc, @Ericlaw says:

    Just as hopeful that those users would download a new browser.. they don't exist on the web either, Vista?.. Windows Server?.. cmon

  30. Hector says:

    What I really don't get is, why, if IE and Spartan are going to share the new and old engines, both browsers are going to be available in Windows 10? Are not they going to be almost the same? At least in the way they present the web?

  31. aa says:

    You CAN NOT put the address bar at top for the phone UI! NO WAY!

  32. Deo - SSGI says:

    So in following suit are they going to renamed the "Administrator" account to "MasterChief"??!

  33. aa says:

    Hector, i wonder the same:

    "Spartan loads the IE11 engine for legacy enterprise web sites when needed, while using the new rendering engine for modern web sites."

    "Internet Explorer will use the same dual rendering engines as Spartan, ensuring web developers can consistently target the latest web standards."

    Sounds to me they will basically be the same, but different UI/name. So more of a marketing thing?

  34. louis says:

    Since XAML+C# has to be protected, there is limited support for HTML5. No vision for the future of the User Interface. Legacy support for Forms, WPF, Silverlight, just to name a few of the "succesfull" UX's

  35. noname says:

    It's a natural thing because main support has ended but will Windows 7 be an end indeed in IE11?

    But the person who says "He also wants you to offer it to Windows 7."may be in the inside, too.

    I think so in the heart actually, too.

  36. slawek says:

    Address bar on top is big mistake. Try to use that on 5" screen device (e.g. Lumia 930) with one hand.

  37. nolonar says:

    I agree with everyone who's disappointed at seeing the address bar on top in the Phone UI.

    As a Lumia 1520 owner, having to reach to the top of the screen to navigate elsewhere is not very comfortable.

  38. Asbjørn says:

    Chrome trolls, please go use Chrome while the rest of us enjoy healthy competition to move the web forward while keeping Google from dominating browsers.

    Spartan looks great. But – I sincerely hope that you simply name it IE 12 and then rename the legacy IE to something like IE (Legacy) and not install it by default. Otherwise, you are going to face a bunch of confused users. That being said, congrats on bringing IE's UI up to date – I hope there's a new extension model, because that was horrible in the old IE.

    Also, I have to agree that the mobile UI doesn't look good – there's too much wasted space.

  39. Adam Lein says:

    Your interface designers need to learn about one-handed usability and mystery meat navigation on smartphones.  Read this:…/8-ways-to-tell-if-your-mobile-app-sucks

    NO interactive elements should be at the top of the screen on a smartphone ever!

  40. Asbjørn says:

    And one more thing – what about developer tools in Spartan? Does it include the much-improved F12 tools from IE 11? If not, it definitely should.

  41. Jonathan says:

    Gotta agree with everyone else here. PLEASE move the address bar back to the bottom on mobile. That's one of the best things about IE11 on Windows Phone today.

  42. Herry says:

    Please move the address bar to the bottom for mobile/phablet

  43. WP8.1 says:

    address bar at the bottom is way better than on top.. please don't change this on mobile just because its more like desktop.  I don't think I'll be upgrading to wp10, you got rid of everything unique about windows phone 8.1!  give me the new browser but keep the address bar and all at the bottom!  dang you Microsoft, always implementing something great only to rip it out in the next version and do something less bold and pissing off your fans that love it.  Just because android chrome and firefox are what people know, most people pick windows phone for a reason!  because it ain't android and ios or the desktop.

  44. Joe says:

    I know you probably will just name it as Modern IE as well, but I think that the address bar on the bottom was really nice even on desktop/tablet windows 8.1, please put the address bar back on the bottom!  thanks

  45. arizdev says:

    MS needs to hire more devs for IE. There is so much to accomplish in an ambitious time frame…

    To MSFT:

    * Will we get a new blog, since it won't be IE anymore? (with a fresh new design!?)

    * Does the spacing get more compact on Proj. Spartan when there's only one tab open? That would look really really really nice like Safari on Yosemite.

    * Pretty please consider implementing Web Notifications, it would go *extremely* well with the release of Windows 10, since Windows finally has a place to put them =)

    To all the complainers:

    * Address bar on top is fine, that's how it is on Desktop as well as 90% of other phones out there.

    * Windows 10 only is fine, it's FREE for the first year, hopefully we see an explosive adoption (in developed countries at least)

    * Those throwing around words like monoculture, variety of doing things, etc. The reason why web dev is hard is because of different rendering engines and 18 ways that your site could end up on different browsers. Let's stop the argument about our f-d situation, we have to deal with multiple browsers. It's a bad and good thing.

    * To those saying contribute to Chrome/Webkit, that is a backhanded slap in the face of hard working people on the IE dev team

    For a dev blog of a major browser, I'd expect more constructive discourse. Thankfully there's #AskIE…

  46. Shrikant says:

    I realy do hope microsot keep the name Spartan. It's already bludering the internet and becomming a famous name. I like and I bet a lot of you do too!

  47. sdsdsd says:

    Address bar top position no!!! Please move to bottom!! Address bar.

  48. addressbar says:

    Your days of comfortably accessing me are over. I will no longer serve the tyranny of the user.

  49. @ IE Blog says:

    Under "Links" in the segment "IE Sites" you find "Exploring IE" which points to

    This link is dead! Please remove it!

  50. Orlandoo says:

    There is no need for another rendering engine. And I hope (but don't believe in) that the first step people will do after installing Windows is to install either Chrome or Firefox.

    @arizdev: >> To those saying contribute to Chrome/Webkit, that is a backhanded slap in the face of hard working people on the IE dev team

    There is nothing bad about slapping in the face of people from IE dev team. They should look to get a job where they can do something useful.

  51. Norman says:

    I can't wrap my head around this "we-have-to-do-it-ourselves" attitude. Especially when It comes down to the rendering engine. Stop doing that. It may be exciting at first but after years of trying it's just sad to watch. This way, if the word about a "new exciting modern browser" comes out of Redmond, you just duck your head and stop listening. It'll go by…

    Seriously, Microsoft. Use something that has proven to be reliable. Something like Gecko. Or Webkit. Google wasn't ashamed to do it either, despite the it being first introduced to Open Source by Apple. This is one of the reasons, Google is dominating the mobile browser market these days. There's nothing wrong about appreciating a good piece of work, even if it's not your own. And if it's really just all about your ego in competition: For god's sake, do it in secrecy. We won't tell anybody, promise.

    With that being said – as Steve Jobs once quoted back in the days: "We believe in the freedom of choice."

  52. Lewes Tiger says:

    Looks fantastic. However, I'm concerned you are throwing away some of the proper design of Windows Phone apps in that I have to get my thumb to the top of the phablet screen to enter something in the address bar. This type of poor design is typical of iOS and Android apps and is being widely copied. One of the worst incarnations of this is the burger menu button at the top right of apps or mobile web sites, bit at they are on the right, whereas your refresh button is tip left. Can we have an option to move the address bar to the bottom of the screen on mobile?

  53. 文科 says:


  54. MacTavish Freeman says:

    Shame on mobile there are both bars at the top (address bar) and bottom (app bar with commands). The clean simplicity of IE on WP 8.1 was great.

    Dude you seriously should make Spartan easier to use on the mobile platform. A UI like this would anger tons of Mobile IE lovers. Just put the address bar on the bottom, and hide the app bar by default, please!

  55. ROWLI says:

    WEBRTC…anything on that..?

  56. mojtaba kaviani says:

    I think project Spartan winner when:

    1. Maximum support html5 and css3

    2. Support extensions and apps in store

    3. Easy develop extensions with visual studio javascript and c# project template that can access cortana , .net, office and services

    4. Voice commands such as scroll up and down , close tabs and more  

    5. Advanced and comfortable developer tools

    6. Automatic and partial update

    7. Themeable and advanced options(flags)

    8. Cross platform and mac, Linux, android and other versions

  57. andrewz says:

    Please implement content wrapping based on zoom level of the page like Opera or Dolphin has.

  58. TÁBéla Csá says:

    Can i instal on windows xp sp2 32 bit? 😀

  59. Spartan Forever says:

    Don't call it Internet Explorer!


    Spartan is the future! (Call it Spartan! One word names are cool!)

  60. Otto says:

    Everyone is preferring currently Chrome because of its speed. Even with Windows XP it's 100x faster than newest IE11 on Windows 8.1 (jQuery DOM/append/offsetWidth, etc)

    Please make Spartan as fast as possible for HTML5 and JS and you're my heros.

    Maybe even some jQuery Native Support?

    Keep on the good work. Best decision to leave IE11 as it is and go for a new browser.

  61. Василий из России says:

    Feel free to ask, and to rejoice?

    Produced another ***, as we say. Maybe it's time to reconsider the concept or simply abandon this venture?

    Marketers 5 points … sold at the price of a regular update the product.

  62. Tom says:

    Will we be able to add/edit styles from the F12 tools like you can in Chrome? That is a must feature!

  63. Shawn Zhang says:

    I think the browser is awesome and can't wait to have a try. Actually Chrome is not a perfect browser due to its week supports for touch and HD screen. It sucks that Chrome kills all my RAM. So I can't agree with those saying IE team waste their time and should contribute to WebKit/Blink. 说句中文,我最看不过自以为是的人。

  64. Shawn Zhang says:

    Sorry, it is "weak" not "week"

  65. Kevin says:

    @Otto "jQuery Native Support" WTF? Consider advocating for modern DOM API support to make jQuery even less necessary, especially if you value speed as much as its seems you do from your comment.

    Anyhow, Microsoft please provide support for Web Components, and ramp up the support of CSS features such as Filters to this new browser. Traditional developers are obviously usually more active in creating tickets than web designers and other content creators of voicing their desire about things like the latter. It's usually too late when they get angry about what's omitted.

    This is even more complicated since many creatives don't bother much with Microsoft's platform which has  somewhat shifted with Microsoft's latest efforts such as Surface Pro and Wacom's Cintiq Companions. has a lot of CSS/Design-centric new features ticketed other browsers have long supported that  IE still doesn't that support that'll be really useful when accumulated such as object-fit, and intrinsic/extrinsic sizing properties

    Hopefully they are not ignored because of numbers on

  66. Brian LePore says:

    @Jeffrey Gilbert,

    Just to be clear, the 5.5 rendering engine is quirks mode. It's the mode that _every_ web browser loads when there is no doctype present (every engine has copied IE 5.5's bugs and loads sites in quirks mode when no doctype is present). That is why it's included in the list of engines that are still supported in rendering. It's not that MS made a decision to go that far back for support but decided to skip the IE 6 engine for some odd reason (though truthfully anything they could do to kill the IE 6 engine would have been a good thing).

    Overall, I welcome this change. I just wish we had more details explaining when the engines were switched.

    I just noticed. It looks like the refresh/reload button was moved. What's the reasoning for that? I always liked it where it was.

  67. Shashi says:

    I strongly suggest to keep just one engine in Spartan…new rendering engine for modern web sites….Including more then one rendering engine will lead to big confusion. For Compatibility  there is IE 11……Enterprises will use IE 11 for legacy web sites and Spartan for all modern sites.

    Keep it simple.

  68. Shashi says:

    Also for Mobile version of Spartan…Please move the address bar to the bottom like IE on WP 8.1….This is better as it will be easy to use one handed on 4inch to 6+ inch phones

  69. I can't believe... says:

    …the number of morons on here (and the rest of the web) that think Google (of all the crap companies to pick from) is the end-all-be-all of the web.

    I like Firefox. Chrome, eh, is tolerable to me but I get the appeal of people liking it. Likewise for Safari and Opera. But they ALL have different engines. The ENGINE IS NOT THE PROBLEM, and IE team is trying to demonstrate that.

    The problem, folks, has always been the lack of standards compliance– by engines AND by web developers. First it was IE not following standards– so they changed. And when they did, web developers said, "crap, we have nothing to complain about, so we better start writing sites that break in IE, because it sucks!"

    STOP THE INSANITY! Write standards-driven web content, stop designing for the legacy browsers, and the world will catch up… whether they choose Chrome, Firefox, Safari, Opera, IE11, or Spartan is irrelevant, because those engines will be forced to be standards compliant in order to work for YOUR SITES.


  70. tk says:

    Will Spartan support ShadowDOM and WebComponents ? It's the most important new web tech I'm waiting for. It's like WPF for HTML ( see )

  71. Evgeniy OZ says:

    please add Spartan to

  72. pmbAustin says:

    I sure hope you're adding a touch gesture to rapidly return to the top of a long page (and/or rapidly scroll to the bottom).  With the number of "infinitely scrolling" web pages out there (Facebook, Twitter, many Tumblr layouts, etc., etc.) it's extremely tedious — ESPECIALLY on the Phone, but also on the Surface — to endlessly flick just to get back to the top or down to the bottom.  PLEASE consider doing something amazing like adding "semantic zoom" to be able to shrink the extending rendered portion of the page down to fit on the screen, and then just touch where you want to zoom into.  That would make navigating long web pages amazingly easy and powerful… better than any other browser.  If you can't do that, then at LEAST provide an area to touch to rapidly scroll to top like iOS/Safari does with touching the status bar.

    Also want to add my vote for keeping the address bar at the bottom, and all the controls easy to reach with one hand on 5"-6" screens as best you can.  Usability!  

    And another vote for just keeping the "Spartan" name if you can (copyright/trademark/etc. and all).

  73. ieblog says:

    The January preview build is now available! Check out the details and try it out for yourself:…/january-build-now-available-to-the-windows-insider-program

    We'll be deploying updated images to RemoteIE in the near future so you can test with the latest build from anywhere.

  74. The animation is driving me crazy. It is a diagram and I want to study it. But it keeps removing what I want to study.

  75. Siyam says:

    Please put the address bar below for Windows Phones. It was the best thing about mobile IE.

  76. Ron says:

    Simpler, with less legacy plugin support, faster and better scurity….

  77. RubenRios says:


    Hi Eric!

    We are working to enable HAR export in the network tool. Stay tuned.

    Regarding the network emulation question, we'll look into this for a future release. Please vote for it in our User Voice site if you haven't do so already:…/84475-f12-developer-tools


  78. __hAl__ says:

    Where in the new build is spartan located.

    I can see the fast rendering engine in Internet Explorer but not find the new browser.

  79. noname says:


    Spartanは当然、メインサポートが終了したWindows 7への提供は無いですよね?

    Windows 7はもうこのまま、IE11で終了でしょうか?



  80. noname says:





  81. Kim says:

    Since I leave near a town with 'Spartan' in its name, there's a lot around here named Spartan-something-or-other. Hmmm, guess you can't copyright "Spartan." I just hope it does not go the way of the SkyDrive and end up getting renamed…. On another note, I'm still supporting a lot of SharePoint users who have trouble with IE11. Wonder how this new browser will support SharePoint functionality? It would be frustrating for users to have to switch between two different browsers, depending on what they're working on.  

  82. warrens says:

    Moving the address bar / refresh to the top of the screen on mobile devices is not an improvement.  Having it at the bottom will let a user keep using their smaller phone one-handed.  I get that you're trying to create a similar experience between all the devices, and that's a fine goal up to a point — but we don't use all our devices in the same way.  

  83. Line says:

    Internet Explorer Spartan sounds good actually… In my opinion, it sounds better as a version name rather than a completely different one.

  84. NumbStill says:

    To all of the ones that write that a top address bar on mobile is a bad decision –

    What do you do more, scroll a page, or use the address bar?

    Having the address bar in a place where a user could have scrolled (thus making the user move their finger upwards in order to scroll) looks somewhat counterproductive to me…

    If anything, the new bottom bar should be removed, I think.

  85. yogesh says:

    nice and gud to see

  86. Mohsen says:

    if can add more demo from spartan

  87. __hAl__ says:


    The address bar below the page does not interfere with scrolling for me

    I would like it to stay below

  88. Colin says:

    to those to recommend WebKit, given the number of times mobile Safari crashes on the iPad I take it you are joking .

    Like the mobile IE look, I guess i'm lucky as I have two arms, but please add gestures to quickly nav to the top or bottom of a page, a refresh mostly positions itself back to where the page was and i'm normally looking to either get back to the sites main navigation or down to the comments.

  89. Klimax says:

    "2.Public Internet web sites will be rendered using the new engine and modern standards, and legacy Internet Explorer behaviors including document modes are not supported in the new engine. If your web sites depends on legacy Internet Explorer behaviors we encourage you to update to modern standards."

    How is compatibility then handled? There are tons of old websites, still used. Just VB forum software is very common. (You want to see crazy things? Check out 3.x version. It is going nowhere…)

    Or will we have just disable thoroughly new engine to avoid problems? (No doc mode? Frankly, idiocy…)

  90. Daniel says:

    Who cares? Really, WHO cares? Yet another shitty MS browser that we'll have develop for because MS have too much ego to simply adopt webkit. On top of that, for at least another two years we'll have to design for both old IE and new Spartan.

    It looks ugly, really ugly.

  91. A.Zaied says:

    Microsoft must develop an Android version.

  92. Viktor Krammer [] says:

    I prefer to have the address bar at the bottom on Windows Phone and on tablets / Surface Pro. What will happen to the modern UI version of IE? actually the modern app was quite good for tablet / touch use. will the modern IE app also be available besides Spartan and desktop IE?

  93. Fabio Duarte says:


    Make those top and bottom bars retractable and LET OPEN IN ANOTHER TAB OPEN THE DAMN TAB IN BACKGROUND!!!

    For God's sair, if I want it opened in another tab it's because I don't want to see it now!

  94. Sergio says:

    So there're two news here. A new rendering engine (probably a good thing). And a new UI. So far I feel that the UI has compromised usability.

    Address/search bar on top seems unfortunate. IE11 on WP had really nailed it by placing it in the bottom… I share pages much less often then I search the web/enter URLs.

  95. Mark Rendle says:

    Want it now!

    That is all.

  96. Joe Kahl says:

    Enterprise constrained: Can I keep IE 9, our corporate standard, and install and play with Spartan on my enterprise Windows 7 work station?

  97. __hAl__ says:

    @Fabio duarte

    If I want a page opened in antother tap i want that to be active and keep de current page in a background tab.

    As most people probably do.

  98. Mityador says:

    Could you please also unveil (e.g. in some future post), what impact this browser and rendering engine duality will have on the programmatic interfaces (IWebBrowser2 et al.)? Or shall be there some new API to embed browser in 3rd paty desktop apps?

  99. Nlp says:

    I Think IE Address bar search method very weak in comparison with Firefox.

    +without quick available website history ?

  100. Yannick says:

    Amazing work, I'm looking forward to the release! However, before you do so, please put the addressbar back on the bottom, where it should be. 😉

  101. @Tom 1/23/15 2:33 PM

    You should be able to add and edit styles in the DOM Explorer. The styles panel is just on the right hand side and clicking should edit and you can use a context menu to add a new item.

    @Domenic Denicola    1/22/15 5:59 PM

    Promises should be instrumented for async call stacks.

  102. oa30 says:

    IE dev team.  First, congrats on producing a cool new browser!  Second, please keep with Modern UI standards and layout.  As another person said, having the address bar at the top is going to be a very hard UX for those with 1520's and other large screen Windows Phones.  The buttons at the bottom (where Share is, etc.) aren't showing the correct Modern UI buttons (round with icons in middle)….please use the established Modern UI round buttons!  Thanks!

  103. kpo6969 says:

    On build 9926 is this normal that when checking your recent activity on your Microsoft Account under security and privacy settings when it shows your sign-ins it shows Chrome as your web browser instead of IE ?

    Thank you

  104. George Birbilis says:

    Will you keep the same bad practice of embedding Flash support (as in IE Metro) but not Silverlight?

    This is a real #fail from Microsoft, especially when HTML5 support is still not established and even mature enough to implement something like ClipFlair ( for which I had to choose Silverlight (and I'm very happy with the result) when it started arround 3-4 years ago

  105. GDev says:

    How About "WebBrowser Control" developers?  I'm wonder to know about interoperability, APIs, etc. Where I can read about?

  106. Smooth Streaming says:

    Apart from DASH how about also adding Smooth Streaming support without having to use Silverlight or Flash? Could get the needed code from the IIS team which makes available SmoothStreaming MediaElement library for .NET/Silverlight (that one also supports DASH now)

    At we have for example a video library in SmoothStreaming format and I see no way to transcode to DASH without getting forced to use Azure or use some extra third-party encoder (we have Expression Encoder Pro that MS stopped supporting to promote Azure Media Services) or without wrapping it to HLS on the fly (which has performance costs for the server). Transcoding to HLS is probably an option, but fills up the filesystem with filechunks, so I'd prefer MPEG-DASH via the TransformManager on IIS (paying for cloud encoding is not an option when you have an R&D project [say an EU funded one] that gets most funding for a certain period only and has to keep on working for years after that)

  107. Louis says:

    Make Spartan available for Windows 7 & 8.1 >> Enterprises won't upgrade their OS within years.

    Chrome even runs on XP!

  108. Steven Willett says:

    From the looks of it, Project Spartan is looking amazing, for those developers complaining "not yet another browser" well develop 1 for all i.e. responsive.

    The Spartan UI looks in keeping with the Microsoft theme and looks very user friendly, I cannot wait to get my hands on this ad test the features it will boast.

    As a MAC fan to date, I am almost at the point of needing to admit W10 will convert me upon final official release.

    Keep up the good work Team MS

  109. Masud says:

    i just wanted to suggest a Name for Project,

    How About 'Enterprise'?

  110. A. Reader says:

    Will Spartan support HTA?

  111. Majid Equbal says:


    This is looking awesome

  112. tbone says:

    The more I think about it, the more I see the layered meaning behind the name.  //name/development_philosophy/mindset.  And it's just cool.  To borrow from Ryan Hayes, "Make it so!"

    Spartan, adj.

    a.  Rigorously self-disciplined or self-restrained.

    b.  Simple, frugal, or austere: a Spartan diet; a spartan lifestyle.

    c.  Marked by brevity of speech; laconic.

    d.  Courageous in the face of pain, danger, or adversity.

  113. @tbone says:

    I just see Halo spartan supersoldiers

  114. says:

    @Sergio and others who gave feedback regarding the mobile UI: We're continuing to evolve the UI and encourage you to give feedback at UserVoice!…/6993955-keep-the-spartan-address-bar-at-the-bottom

    @Evgeniy OZ – You can try out the new rendering engine today in Remote IE using the Windows 10 Technical Preview. We'll continue to update the engine and add Project Spartan to Remote IE in later updates. Stay tuned!

  115. says:

    @arizdev We're working on some updates to our blog and other web properties in the coming months – stay tuned!

  116. Mike Gale says:

    Would be good to see a single answer to all of @EricLaw's points.

    From my perspective I'd love the ability to make the browser my own.  Access it programmatically so that it can do what I want (rather than what some hypothetical "consumer" might want).

    I don't really want some sandboxed, JavaScript only, way of talking to the machine.  What I want is a way to access the browser from .NET and maybe Powershell code, that integrates it with my own custom desktop tools.

    I know there's an overwhelming tendency to dumb the Internet down, but there's a need, for many, to treat the browser as a serious tool.  We feel abandoned in the mad scramble for easy, mindless and "you have no way to do your own thing".

    What is going to offered in this space?

  117. Mike Gale says:

    Oh yea.

    The remote browser version disconnects fairly often so testing with it must be limited.  Will this improve?

  118. Zay J. Speed says:

    Can I just go back to "Windows Memphis "  now? it is what Elvis would want!

  119. Rafael Ferrete Ruiz says:

    looks good, hope it works well

  120. says:

    希望ie還是能出新版本 ie真的很好用

  121. John Shaw says:

    @EricLaw : taking advantage of the free upgrade to Windows 10, is not a decision to take lightly, as the ultimate deciding factor  for me, will be based not just on my current hardware, but whether all installed software, will be compatible in Windows 10. I have spent thousands of dollars on software, and do not like the thought of having to replace said software, with newer versions (if available) to get it to run in Windows 10.

  122. sunstar says:

    This is a good idea… What will happen to IE?

  123. Rich says:

    15 year web developer here. HTML5: Input type=number… barely works in ie.  No spinners like chrome.  Allows you to type letters.  input type=datetime-local … wouldn't it be nice to have a pop-up calendar, without having to use jqueryui.  "required field": wouldn't it be nice if this worked with standard ajax buttons, and not only submit/command buttons.  Firebug:  I can't web-program anymore without using firebug in firefox.

    Unrelated: MVC still has no grid.  I'm forced to use bootstrap datatables, or pay($1000) for Telerik, as MVC hasn't fully caught up to webforms/ajax toolkit, and certainly not Telerik, in terms of widgets.  Grids with autocomplete searches that download in excel with a few lines of code.  Available, just absent from Microsoft in MVC5/6.

  124. kkkk says:

    Microsoft Internet Explorer Universal Cross-Site Scripting Flaw(0day?)…/internet-explorer-xss.html

    Hurry up!!!

  125. drd says:

    Here's the a draft design for semi-auto-tagging and categorizing download manager – visually it would look similar to the current manager, just have bunch of intelligently pre-filled comboboxes for tags and backend that moved files around the drives such that various types of downloads would end up in the right place if there's many hdd's:

    – download manager with a category/tag field next to each dl that you can fill (or prefilled with previously filled tag)

    – already downloaded (and future) files get moved to path when tag is changed (or new location is made for a tag)

    – the file tagging combo box has auto-complete to find existing tags and is prefilled with tag based on either last tag or dl link url or file name (based on previous dls)

    – dl link url, filename with numbers removed are additional hidden tags

    – remember the dl location so that future dl from same page gets offered the same tag as before

    – options:

    a. create shortcut to the page with the dl link in the same folder as the file, or put it in ntfs alternate data stream accessible through right click of the downloaded file

    b. save also page with download link to mht and take screenshot, to be able to read longer descriptions of file content when offline or when page is no longer available

  126. drd says:

    Here's another thing the new download manager needs:

    Eg. this page has dozen+ "download" links.

    vvv postsharp net/downloads/samples/2.1

    When you click the download link that points to a .zip file, instead of .zip you get to another page that has another download link that starts the download. (Just like Microsoft Downloads not too long time ago for several years, except in Microsoft Downloads there was even more pages to go through before you got to the real download link)

    So the new IE12 download manager should be like this:

    On that samples/2.1 page linked above, you need to be able to select all these "fake download links" and have the download manager then go through the real download link on the 2nd page.

    There is no nice general solution I can think of besides

    1) to recursively go through and download every link on the subsequent pages and then have the user select which file extension is the one they want to save. Anything else is prone to break because the browser has no way to know what links are really links to downloads. So pre-load say 4 KB of each link associated with visible text or image beyond the pages behind the first click and then if users says "no these aren't zip's", then recurse further. Really ugly but this I don't believe there is any other way to have a general solution to this problem where the real downloads may be hidden behind multiple interim pages.

    2) to go to peek the first link of the multiple selection, then have user click the real dl link, then if it turned out another fake link, click the link on the 3rd page (still trying to dl the first zip). Now if it was the real download, use heuristics to mimic the user action in attempt to download the other zips incase they also need recursing multiple pages to find the real dl link.

  127. sankara says:

    good achievement.

  128. NumbStill says:

    @drd –

    Please, use this UserVoice for user interface feature requests –…/87567-internet-explorer

  129. Anonymous says:

    This look good, but can't height of address bar be more thin so there is more room for webpage

  130. Tunsafun says:

    If you are bitching about wasted screen space, it might be time to upgrade your monitors

  131. Perry says:

    It's tough to get rid of IE, that name is exactly what it is for.  I hope Spartan does not confuse users with the name.  I use many browsers for my needs, from Mozilla Firefox, Chrome, Safari, to IE 11.  They all have their strengths and weaknesses.  I like to right-click to resize the search line so that I can get most of the page or move that search line around.  Also I like to keep things typed in the search line while browsing pages as a way to customize the browsing experience.  I like a different backdrop of the web page, like having a sunset background on the browser menu bar.

  132. Jeffrey says:

    Haven't used IE for years and this sure isn't showing any reason to return to using a MS browser. MS really needs to learn a PC is not a  phone or tablet, so stop trying to make them all the same! While an integrated search/address bar is practical for a mobile device it was the first reason to go away from IE.

  133. AL says:

    Should change IE to IV for Voyager. It sounds great.

  134. Simon says:

    Who cares? You only try because you lost the market to Chrome and Firefox. Might as well keep out and stay out.

  135. Vitor Canova says:

    Well @Simon. Netscape lost their market to Internet Explorer, they change the name and their attitude and now Firefox is a great browser.

    Some guys, like you, even quote that now Firefox has more market than IE, incorrectly of course.

    If you don't like just left us alone and continue to write your prefixed code.

  136. unimportant says:

    Your mantra should be 'compatibility'. That's the only – emphasis only – thing you should be worried about. Get that right, and then you can start putting bells and whistles on it. IE has been an albatross on the web dev industry since forever.

    While you are at it – backport devtools upgrades to IE9+ too! Clean up your legacy before dropping new products, and help give your immense user base better experience by supporting developers who have to in turn support them.


  137. Muizz says:

    I couldn't find spartan in windows 10 latest version .How can i find .Will i have to downloaded it

  138. Vitor Canova says:

    @Muizz Spartan in its full form is not available in the current built (10041).

    IE team promiss they will try release it in the next build to be released next month (probably).

    In the current build you can just use the new Edge engine by enabling features in about:flags.

  139. active windows build 10049 says:

    please serial for active windows after install build 10049  tanks

  140. Mike says:

    Sounds good. Just think it should be up to the user what they want on the computer. Windows 10 seems to force stuff on people without giving them the choice to uninstall things. Like I don't want to use Onedrive but I can't uninstall it. Same with IE and Spartan. Its like its forced on people. Windows Explorer seem more things that I would never use. I still like Windows 7 better than 10.

  141. degree6 says:

    The Spartan experience doesn't seem the best as it lacks a search bar.

    As the search bar ends up only sort of working inside the address bar (instead of separate where it belongs), the two fight with each other and the performance/utility of both is diminished.

    Please make it like Firefox, which i will just keep continue using: have a search bar added.

  142. Techsupport says:

    AH, IE 11 barely works with websites, constantly use compat view, and that usually fails, trying to get IE 11 to work as a older version IE 7 mode. That is why most people use Google Chrome, FireFox. It is great the Microsoft is trying to lead the way in, and dictate how developers should create websites, and not share the Intergrated broswer, and OS code, so the website can be delevoped to work with IE 11. Sounds like a marketing scheme, with the same results, "Page Cant be Displayed" that message should include, "Page cant be displayed, try Chrome, or FireFox".

  143. talha says:

    Great Info, But I think it's not better than Google Chrome and Firefox as shown in the video review here

  144. WERTW4R says:


  145. Jeff Ryan says:

    I'm assuming that built-in language translation is coming in a future build. As an international business and traveler I ended up installing Google Chrome for this feature after receiving Spartan through the Windows 10 Preview on my Surface Pro 3 while in Japan last week to get this feature. It was very cumbersome to have to go an external resource to translate a web pages' content before meeting with a client.

  146. Tom Anton says:

    I have question, i hear from Autodesk that new IE , will support opening filest from Autodesk  2D and 3D  only by using browser , is that true ?

  147. zzzb123 says:

    while it looks ok, I prefer the design and function of IE 11.  while this Dual engine rendering crap is interesting, IE 11 already does it.  I see no improvement.  instead of using this to phase out IE, simply offer it as a UI change in the  PC settings.  while IE has not done well, I don't think its past should stand in the way of a bright future.  I am using IE right now and loving it.  If you are going to have win10 come with both internet browsers, let people know this during the setup procedure of either browser, and allow the people to choose which browser they prefer.  I choose IE.  good luck Microsoft, while it is not the best it can be, it shows you are attempting to show the improvments made in your browsers since IE 9, and they have been huge.