One of my friends wrote a post about how much he saves (or could save) by biking to work every day based on the distance to and from work, and the average gas price over the entire year and how far his car can go per litre of gas. It seemed like an interesting thing to build a calculator out of. Obviously it is more useful to be able to calculate out your own savings instead of just seeing how much your friend is saving based on his maths (and his vacation days).

I added a few things like how much CO2 you were not pumping into the atmosphere and lots of toggleable fields to play with. This is what it looks like with the basic data filled in:

Go play with it here, see how much money you could save by biking to work (or anywhere that you would normally be driving to daily). The code is available on github if you want to suggest changes or fix something. I didn’t write any tests for the maths, so there may be bugs because of things I didn’t consider.