Show HN: Compare different lenses on different camera sensors

I've calculated for some time different focal lengths on different camera sensors, based on sensor size and pixel count by hand.

To make this easier for me, I've written a small JS tool to calculate the equivalent focal length for lenses on different sensors:

http://www.buyersguide.me/lens/

It might help you with your next camera and lens buying decision. Enjoy and happy GAS :-)