How much power do I need to climb?

On a typical 8% climb at 15 km/h with 80 kg total weight, you need about 280-300W. Steeper gradients require significantly more power at the same speed.

Why is gravity the dominant force on climbs?

On steep climbs at lower speeds, gravity accounts for 80-90% of total resistance. Aerodynamic drag becomes negligible below about 15 km/h.

Does bike weight matter much on climbs?

Yes. On a 10% gradient, saving 1 kg of total weight saves roughly 4W at 15 km/h. This becomes more significant on longer, steeper climbs.

What total weight should I enter?

Enter the combined weight of rider, bike, kit, bottles and any luggage. A typical road setup is rider weight plus 8-10 kg.

BikeCalcs

Climbing Power Calculator — Power Needed to Climb

Calculate the power needed to climb at a given speed and gradient.

Total Weight (rider + bike)

Gradient

Climbing Speed

Crr

Road tyre ~0.005

CdA

Climbing position ~0.35

How We Calculate This

Climbing Power Formula

Total power required is the sum of three components:

Gravity: P_gravity = mass x g x gradient x speed
Rolling resistance: P_roll = Crr x mass x g x speed
Aerodynamic drag: P_aero = 0.5 x air_density x CdA x speed^3

Frequently Asked Questions

Related Calculators

Watts Per Kilo Calculator

Calculate your power-to-weight ratio in watts per kilogram.

Power to Speed Calculator

Estimate cycling speed from power output accounting for all resistances.

Drag Calculator

Calculate aerodynamic drag force at different speeds.

CdA Calculator

Estimate your drag coefficient area from field test data.

Wind Resistance Calculator

Calculate the effect of headwind and tailwind on power requirements.

Last updated: February 2026

All calculations are estimates. Always verify results and consult a professional bike fitter where appropriate.