Browser tricks: simple calculator at your fingertips

So my wife and I got a treadmill not too long ago, and one of the nifty things it has is support for heart rate monitors. The thing actually includes one, so I set out to learn how best to use it.

I came across pages like this one, most of which have an assortment of simple formulas to target your maximum heart rate, recommended, etc. Drawing inspiration from a recent post about toggling MSDN pages to low-bandwidth mode, it was simple to just press Alt+D to go to the address bar, and type javascript:alert(220-28) to get my maximum heart rate as per formula #1.

Of course, I can never leave well enough alone. So I bookmarked a random page, renamed the favorite to ‘My max heart rate’, and then right-clicked, selected Properties, and add a more complex expression, such as javascript:alert(220-(new Date().getYear()-1980), which should hold up through time 🙂

Now I have a favorite that will forevermore give me an updated value for my max heart rate. Which may be overkill if I could just remember the formula, hehe. 


Comments (1)

  1. Nice trick, I’ll make use of that one 🙂

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