Cycling Power to Weight Calculator

Power to weight is your power output divided by your body weight in kilograms, expressed as watts per kilogram, or W/kg. It normalizes raw watts against how much mass you have to move, so a light rider and a heavy rider can be compared fairly on the same climb.

It does one thing precisely: it computes watts per kilogram as power divided by weight in kilograms. It does not estimate climbing time, speed, or FTP. It just gives the ratio and the kilogram weight that ratio was based on.

As a rough guide at threshold, many recreational riders sit around 2 to 3 W/kg, fit amateurs around 3 to 4, strong club racers around 4 to 5, and elite professionals above 5 to 6 W/kg for a sustained hour. Your own value depends heavily on the duration behind the power number.

Use whichever matches the comparison you want. FTP or 20 minute power reflects sustained climbing and endurance. A one minute or five second peak reflects sprint and attack ability. The math is the same, only the power number you enter changes.

When the unit dropdown is set to lb, the tool multiplies your entry by 0.45359237 to get kilograms, then divides power by that figure. So 154 lb becomes 69.85 kg, and the Weight used box shows that converted value.

On a sustained gradient most of your effort goes into lifting body plus bike against gravity, which scales with total mass. A higher W/kg means fewer watts are spent carrying each kilogram, so for a given fitness you climb faster. On the flat, aerodynamics and raw watts matter more than the ratio.

The full precision division is done internally, and both the W/kg result and the kilogram weight are displayed to two decimal places. So 300 W at 154 lb shows as 4.29 W/kg even though the underlying value carries more digits.

No. The calculation runs entirely in your browser with a simple division, and nothing you type is uploaded or stored. You can use it offline once the page has loaded.

For the standard rider W/kg figure used in training charts, enter body weight only. If you want a total system ratio for a specific climb, you can add bike and kit weight into the weight field, but that number will not match published rider benchmarks.