Tired of carrying a gear chart to the velodrome every day, or searching the web for one every time you change gears? Then you need a gear calculator on your phone.

Built by track racers for track racers, the Track Gear Calculator supports chainrings from 44 to 56 teeth and cogs from 12 to 20 teeth.

Want a bigger gear or a smaller gear? Track Gear Calculator works in reverse, too: just swipe the gear inches, and you'll get a new gear, up or down from where you are, using only the chainrings and cogs you have with you. You can also select from the standard 27" nominal method for calculating gears, or more accurate actual wheel diameters.