Cycling Power Calculator
Calculate and classify watts/kg
3.29 W/kg
Moderate (Recreational)
Training zones
Why watts per kilo?
A heavier rider needs more power to climb at the same speed. Watts alone therefore say little — only relative to body weight do riders become comparable.
The calculator divides your power by your weight and places the result on a scale from beginner to world class.
How it is calculated
Watts per kilogram = power in watts / body weight in kg. If the power you enter is a 20-minute value rather than your FTP, the calculator also estimates FTP with × 0.95.
On a climb it is not absolute power that counts but what each kilogram of body weight has to move — which is why W/kg is the number that lets riders of different builds compare.
Example: 230 W FTP at 70 kg. 230 / 70 = 3.29 W/kg — the calculator rates that as Moderate, solid recreational level.
The rating: from 3.2 W/kg Moderate, from 4.0 Good, from 5.0 Very Good, from 5.6 Excellent, from 6.4 World Class. The steps follow racing categories and refer to a 60-minute FTP.
To calculate W/kg, weigh yourself in the morning before eating — a 2 kg difference shifts the value at 230 W by almost 0.1 W/kg.
When the number matters
On a climb, watts per kilo decide almost everything. On the flat and in time trials absolute watts matter more, because air resistance dominates there.
A heavy rider can therefore be faster on the flat and slower uphill than a light one, at the same rating here.
Frequently asked questions
- Which power value should I enter?
- Your FTP is the most meaningful — power over roughly an hour. Short sprint numbers produce a figure that says nothing about endurance.
- Is losing weight the faster route to higher watts per kilo?
- On paper yes, in practice rarely. Lose too much and power goes with it, leaving you slower overall.
- Why can't I reach professional numbers?
- Because those combine decades of training, genetics and a full-time job. Comparing against your own value from a year ago is more useful.