I’m into running lately. So quite often I do these calculations in my head “if I ran 10 secs/km faster, what distance would I have covered?” As the calculation are quite difficult and I am quite lazy, here’s a calculator that answers most of my questions. Posting it here for personal use, but maybe it’ll be useful to someone else too.

Usage: fill in any two textboxes and click “calculate” next to the third one.

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