gears.bike
See Your Gears. Really See Them.
You know the range you want. But how does a 10-33 cassette compare to a 10-36 with your current chainrings? Where do the overlaps land? Which gears are you actually going to use?
gears.bike makes it visual. Pick a cassette and chainring combination, and your gear ratios appear on a shared linear scale — spaced exactly by their relative values. Add a second setup and they align side by side. Identical ratios line up. Gaps and clusters become obvious at a glance.
What You Can Do
Compare setups side by side — put your current gearing next to a proposed swap and see exactly what changes.
Switch between ratio and speed modes — view raw gear ratios, or enter your cadence, wheel size, and tire width to see actual km/h or mph per gear.
Search by brand, model, or range — type “SRAM Force”, “11-34”, or “52/36” to find what you need across SRAM, Shimano, and Campagnolo.
Share with a link — every configuration is encoded in the URL. Send it to a friend or save it for later.
Supported Drivetrains
Cassettes — 12-speed and 13-speed from SRAM, Shimano, and Campagnolo, including road, gravel, and MTB ranges.
Chainrings — 2x and 1x setups from all three manufacturers, from compact 43/30 road to 52T single rings.
Use It
No account. No install. Just open it in your browser.
Privacy
gears.bike collects no data. Everything runs in your browser. Nothing is transmitted or stored.
Support
Questions? Email support@portcity.tech .
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