2x vs 1x Bike Gear Conversion Calculator

Please select your current and wanted setup

Data shows chainring/cog ratios, and speed at cadence 90 in parenthesis for a 29" (700c, 622mm) wheel size. The Diff column shows red for slower/easier gear, and green for faster/tougher gear. The color is not an indication of better/worse, but merely a visual aid to show how your selections affect the ratios.

For example, if you change a 50-34 chainring to a 42 but keep a 11-28 cassette, your lowest gear (42 - 28) will have a tougher ratio (feels heavier), but you'll ride faster with it. Your highest gear (42 - 11) will have an easier ratio (feels lighter), but you'll ride slower with it (given the same cadence).

Blue colors indicate "most used gears" (e.g. one seldom rides with the smaller chainring & smallest cog on cassette). The comparison in the Diff column is made between your chosen 1x cassette (orange), and the blue cells from your 2x setup.

Often, when doing a 2x to 1x conversion, a combination of a 1x chainring and a cassette is sought so that the ratios fall pretty much in line with what the rider is used to in the current 2x setup. Fine tuning can then be applied if the intention is to e.g. change riding style (from road to gravel, hillier/flatter routes, etc.)

Cadence = revolutions of the crank arm per minute.
High gear = high ratio = smaller cog on cassette
Low gear = lower ratio = bigger cog on cassette

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