Chainring/Cog Combo Calculator

How It Works

Modern road bikes use compact (50/34), mid-compact (52/36), or standard (53/39) chainring pairs with 11-28, 11-32, or 11-34 cassettes. Gravel bikes often run 1x with 40-42T chainring and 10-42 or 10-52 cassette. MTBs are almost all 1x now: 30-34T chainring with 10-51 or 10-52 cassette. The key is gear range (ratio between highest and lowest gear) and the gaps between gears. More cogs (12-speed) means smaller gaps. Cross-chaining (big-big or small-small) wastes energy and wears the chain.