Cycling Power-to-Weight Ratio
Calculate your cycling power-to-weight ratio (W/kg) and see the Coggan classification, from untrained to world class. Enter power and body weight.
W/kg + class
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Power-to-weight ratio in cycling
The W/kg ratio is the cyclist's FTP (Functional Threshold Power, in watts) divided by body weight in kilograms: W/kg = FTP / weight_kg. A 75 kg rider with FTP of 300 W has 4.0 W/kg. Reference brackets: <2 beginner, 2–3 recreational, 3–4 trained amateur, 4–5 racing category, 5–6 elite amateur, 6+ professional. Tadej Pogacar holds about 6.4 W/kg sustained over 30-minute climbs in the Tour de France.
Applications
Comparing riders of different sizes (heavier riders need more raw watts for the same W/kg), classifying climbs, deciding whether to upgrade racing category, and setting your Zwift level — categories B/C/D are gated by W/kg thresholds. On flat terrain raw watts matter more; on climbs W/kg dominates.
FAQ
How do I measure my FTP? The classic protocol is a 20-minute all-out test; average power × 0.95 is your estimated FTP. Smart trainers and platforms like Zwift, TrainerRoad and Garmin automate this.
Should I lose weight or gain watts? Both raise W/kg, but losing muscle hurts absolute power. Below a certain body fat threshold, gaining watts becomes the only sustainable path.
Is 4 W/kg good? Yes — it puts you in the racing-category amateur bracket, above ~90% of recreational riders.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.