This app enables you to calculate the gear ratio in gear inches of different fixed or single speed configurations, and then compare this set up instantly with nearest equivalents using different chainring sizes. This is really handy when planning your next fixed gear conversion, or just for the intrinsic interest in comparing different set ups really quickly, and takes all the trial and error out of selecting a sprocket size to match any available or desired chainring size.

If you know what works for you or a friend with a given chainring size, and you are thinking of changing to a different chainring size, but preserving a similar gear ratio, then this is EXACTLY what you need.

Now includes chainring sizes from 34 to 54 inclusive. If you are interested in BMX sizes please check out the companion app at https://play.google.com/store/apps/details?id=com.westcoastwebworks.bmxgearratiocalculator

Simple, elegant, efficient, and reliable; if an app could be a bicycle this one would be a fixie...