Cycling calculator
Power to weight ratio calculator
Work out your watts per kilogram at FTP and over 5 seconds, 1 minute and 5 minutes, and see which rider category the threshold figure lands in. Free, instant, no sign-up.
The three peak durations are optional — leave blank what you have not tested.
Watts per kilogram by duration
Category tables vary by source. These bands are rounded from Coggan's power profile chart, they describe a rider population rather than a licensing standard, and no federation hands out a race category for a power number.
There are two ways to move this number, and the coach will tell you which one is yours.
What is power to weight ratio?
Power to weight ratio is watts divided by body mass in kilograms, and it is the number that decides how fast you go uphill. On a steep climb almost all your power goes into lifting yourself against gravity, which scales with mass — so a 60 kg rider at 240 W and an 80 kg rider at 320 W climb at the same speed. On the flat the picture inverts: aerodynamic drag barely cares what you weigh, so raw watts win and the heavier rider is faster.
How this calculator works
Each power figure is divided by your body mass, converting to kilograms first if you entered pounds. FTP is the durable one — it is what a climb, a breakaway or a long solo effort is decided by — while the 5-second, 1-minute and 5-minute numbers describe your sprint, your anaerobic capacity and your VO₂ max ceiling in turn. The four together are what coaches call a power profile, and the shape tells you far more than any single figure: a sprinter and a climber can share an FTP and be unrecognisable everywhere else.
Reading the rider categories
The bands come from the sex-stratified power profile table in Allen and Coggan's Training and Racing with a Power Meter, rounded to the nearest tenth. Roughly speaking, under 2.0 W/kg at threshold is untrained for a man, 3.0–3.5 is a fit club rider, above 4.5 is a strong amateur racer, and professional grand tour riders sit near 6 W/kg for an hour. Women's columns sit lower across the board because the underlying population differs, not because the physiology is different in kind — compare yourself against your own column and, more usefully, against yourself six months ago.
Raising the ratio
There are two levers and they are not equally good. Adding watts is slow but permanent, costs nothing in health, and improves your flat riding at the same time. Losing mass is fast on paper and often self-defeating: cut too hard and FTP falls with the weight, so the ratio barely moves while your recovery, immune function and bone density all get worse. If you are carrying obvious excess, weight is the quicker lever. If you are already lean, stop looking at the denominator and train the numerator.