How does the calculator estimate climb time?

It balances the power you supply against the forces resisting you — gravity, rolling resistance, and a small amount of drag. It solves for the road speed that consumes exactly your available wheel power, then divides climb length by that speed.

VAM (velocità ascensionale media) is metres of elevation climbed per hour. It is a popular way to compare climbing performances across different gradients, with strong amateurs around 1,000 m/h and pros above 1,600 m/h on hard efforts.

What effort percentage should I enter?

For a climb under about 20 minutes you can hold close to or slightly above FTP, so 95 to 105% is realistic. For longer climbs, drop toward 85 to 90% of FTP to avoid blowing up before the summit.

Why is weight so important on climbs?

On a slope, most of your power goes into lifting your total mass against gravity, which scales directly with weight and gradient. That is why power-to-weight (W/kg) predicts climbing speed far better than raw watts.

Does it account for wind or drafting?

No. The model assumes still air and a solo effort. On steep climbs drag is small so this matters little, but on shallow or windy climbs your real time can differ from the estimate.

Cycling Climb Time Calculator

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Cycling climb time calculator

Planning a KOM attempt or pacing an event climb? This tool estimates how long an ascent will take given your FTP and the effort you intend to hold. It uses a full power-balance physics model rather than a rough rule of thumb, so it accounts for gradient, total weight, rolling resistance, and drag.

How it works

Your supplied power at the wheel must equal the power consumed by all resisting forces at your road speed:

P_wheel = (Crr·m·g·cosθ + m·g·sinθ + 0.5·ρ·CdA·v²) · v

The tool derives the slope angle θ from elevation gain over length, sets P_wheel from your FTP times your chosen effort times drivetrain efficiency, then solves this equation for speed v by numerical bisection. Climb time is simply length ÷ v. It also reports VAM, your average vertical metres climbed per hour.

Example and tips

A 70 kg rider on an 8 kg bike holding 90% of a 280 W FTP up a 10 km, 800 m climb (8% average) ascends at roughly 13 km/h for a time near 45 minutes, with a VAM around 1,050 m/h. Choose an effort you can truly sustain for the climb’s duration — overcooking the lower slopes costs more time than it saves.

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