Watts Per Kg Calculator
Find your cycling power-to-weight ratio — the number that decides how fast you climb. Works with FTP, 5-minute, or sprint power.
The basics
Understanding power-to-weight
Why W/kg matters
Two riders can produce the same watts, but the lighter one climbs faster because they carry less mass up the hill. That is why cyclists track watts per kilogram: it captures power relative to body weight, which is what governs performance on any gradient. On the flat, raw watts matter more; the steeper the road, the more W/kg decides the outcome.
Which power number to use
W/kg is only meaningful alongside a duration. Your FTP W/kg predicts sustained climbing, your 5-minute W/kg reflects short VO2 max climbs, and your 5-second W/kg describes a sprint. Plug in whichever power you want to understand, and remember the same rider looks very different across durations.
Improving your ratio
There are only two levers: raise power or lower weight, and the first is usually the healthier, more durable win. Structured training that lifts your FTP moves the number up without any dieting. In Ride Cave, adaptive plans build that power over a season, and your power-to-weight is tracked automatically as both your fitness and weight change.
Frequently asked questions
What does watts per kilogram (W/kg) mean?
Watts per kilogram is your power output divided by your body weight in kilograms. It measures how much power you produce for your size, which is what determines how fast you climb and accelerate.
How do I calculate watts per kilogram?
Divide your power in watts by your body weight in kilograms. For example, a rider with a 250 W FTP weighing 70 kg has a power-to-weight ratio of about 3.6 W/kg. If you weigh in pounds, divide your weight by 2.2046 first.
What is a good power-to-weight ratio for cycling?
At FTP, roughly 2.0–3.0 W/kg is a solid recreational rider, 3.0–4.0 W/kg is a strong club rider, 4.0–5.0 W/kg is a competitive racer, and above 5 W/kg approaches elite. Sprint W/kg (5-second power) is far higher for everyone.
Should I use FTP or peak power for W/kg?
It depends on the effort you care about. Use your FTP for sustained climbing and threshold efforts, your 5-minute power for VO2 max climbs, and your 5-second power for sprints. The same rider has very different W/kg at each duration.