Climb time calculator
How long a climb will take at a given power, and how fast those watts make you go on any gradient. Physics, not optimism — although see the caveat below.
Climb time
How long will this climb take me?
Also gives VAM — vertical metres per hour — which is the number climbers actually compare, because it strips out how long the climb is.
Speed and power
How fast will a given number of watts make me go?
Physics, not a promise: rolling resistance, air drag on the hoods, and gravity. Real roads add wind, surface and traffic, so treat it as the best case.
What is VAM and why do climbers care about it?
VAM is vertical metres per hour — how fast you gain altitude, regardless of how long or steep the climb is. It is the one number that compares a short brutal ramp with a long alpine drag.
Rough bands: under 900 m/h is steady touring pace, 900–1200 is a solid amateur climbing well, 1200–1500 is quick, and above that you are in racing territory. VAM tracks W/kg almost directly on gradients above about 6%, which is why climbers talk about both in the same breath.
Why is the real world always slower than this?
The model knows rolling resistance, air drag and gravity. It does not know wind, road surface, traffic lights, hairpins where you brake, or the fact that you will not hold exactly that power for the whole climb.
Treat both numbers as the best case on a still day. On the flat, wind dominates everything — a 15 km/h headwind can cost more than a 2% gradient. On a climb above 6% the model is much closer to reality, because at 10 km/h air resistance almost stops mattering and it becomes a simple fight between watts and weight.
Want the weight side of that fight? The W/kg calculator shows what losing five kilograms does to the same climb.
Part of ten free cycling calculators — all of them run in your browser, nothing is sent anywhere.