W/kg is power divided by body mass. Enter measured FTP directly; a 20-minute test average is not the same value.
About W/kg Power Profile Analyzer
Divide measured 5-second, 1-minute, 5-minute, and FTP power by one body-mass value to compare your own efforts without applying unsourced competitive rankings.
Compare cycling watts per kilogram across three durations plus FTP
This calculator divides each entered power value by the same body mass so you can compare three fixed-duration efforts—5 seconds, 1 minute, and 5 minutes—alongside FTP on one consistent W/kg scale. It describes your inputs; it does not assign a competitive category.
Use measured efforts that belong together
Enter body mass in kilograms or pounds and power in watts. The calculator stores mass in kilograms, then applies W/kg = watts ÷ kilograms to every row. Switching the global unit preference changes the displayed mass, not the physical rider or any W/kg result.
A useful profile compares representative values recorded in a similar training period. Mixing a fresh sprint with a stale FTP can make the shape reflect testing dates rather than current capabilities. Note whether each value came from a maximal effort, a race, or a formal test before comparing it later.
Use the same body-mass reference for all four efforts.
Prefer recent, well-recorded maximal or test values.
Keep absolute watts beside W/kg when equipment and terrain matter.
Read the shape without inventing a ranking
The three fixed-duration efforts sample different parts of a power-duration relationship, while FTP is a separately estimated power anchor rather than a duration. A single entry does not diagnose a physiological system, and the labels are not sharp boundaries between energy systems.
Compare your own rows over time or inspect which duration changed after a training block. This page intentionally omits population percentiles: rider category, sex, age, test protocol, equipment, and data source all affect a defensible comparison, and the calculator has none of that context.
Keep FTP and short-power tests distinct
Enter measured or separately estimated FTP in the FTP field. A 20-minute average is not automatically FTP, and research has found that common FTP estimates are not interchangeable with every lactate-derived threshold. Use the dedicated FTP tool when you need to apply a named protocol.
W/kg also does not predict road speed by itself. Aerodynamics, rolling resistance, gradient, drivetrain losses, drafting, and duration all influence cycling performance. Treat this table as normalization arithmetic, then continue to the tool that matches the decision you are making.
Frequently asked questions
How is cycling W/kg calculated?
Divide power in watts by body mass in kilograms. For example, 300 W at 75 kg is 4.00 W/kg. Pounds are converted to the same canonical kilogram value before the division.
Is higher W/kg always faster?
No. W/kg is especially relevant when gravity matters, but speed also depends on absolute power, aerodynamics, rolling resistance, gradient, conditions, and how long the power can be sustained.
Should I enter my 20-minute power as FTP?
Not without applying and documenting an FTP protocol. A 20-minute average is not automatically FTP, and different protocols can produce different estimates.