About this calculator

Development = (chainring / sprocket) × wheel circumference. EU road bikes (700×25c) have a circumference ~2.105 m.

Frequently asked questions

What does the Bicycle Gear Ratio & Development do?

Gear ratio and metres-per-revolution for a chainring/sprocket combo. Development = (chainring / sprocket) × wheel circumference. EU road bikes (700×25c) have a circumference ~2.105 m.

Is the Bicycle Gear Ratio & Development free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Bicycle Gear Ratio & Development?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified cycle shop professional before committing to a purchase or a job.

What inputs does the Bicycle Gear Ratio & Development need?

Enter values for: Chainring teeth, Sprocket teeth, Wheel circumference (m), Cadence (rpm). Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Bicycle Gear Ratio & Development on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.