About the Bike Power-to-Weight Calculator
Cycling power-to-weight ratio in watts per kilogram, with the rider category it corresponds to.
Also known as: w/kg calculator, watts per kg, ftp per kg, cycling power ratio.
How to use this calculator
- Enter power (ftp or average), weight unit.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
W/kg = power ÷ body weight
Worked example
Using the values pre-filled in the calculator above:
- Power (FTP or average) = 250 W
- Weight unit: kg
- Body weight = 72 kg
the calculator returns:
- Power-to-weight: 3.47 W/kg
- Category: Enthusiast
- 20-minute power estimate: 263 W
- Power for 5 W/kg: 360 W