Hobbies · Cycling
Cycling climb to flat distance equivalent.
Enter your mass, power, climb gradient and ascent. The calculator finds how long the climb takes and how far you would ride on the flat in that same time at the same power. Example: 80 kg total at 250 W climbing 500 m at 7% takes 30 min 8 s; on the flat the same effort covers 18 km at 35.8 km/h, so each metre climbed equals about 36 m of flat riding.
Your numbers
Result
Working out the result.
How the equivalent is calculated
There is no single standard exchange rate between climbing and distance, because the answer depends on the rider and the road. This page defines one clear version: equal time at equal power. It uses the power equations in Wikipedia's “Bicycle performance” article, P = (½ ρ v³ CDA + v m g Crr + v m g s) ÷ η, with ρ about 1.225 kg/m³, Crr 0.003 to 0.006, g 9.8 and derailleur losses of 1 to 7%. It solves for steady climbing speed on the slope, then for steady speed on level ground with the same power, and multiplies the flat speed by the climb time.
The ratio shown is flat metres per metre of ascent. It is our derived figure from the model, not a published constant. Drag area (default 0.35 m²) and rolling resistance (0.004) are our choices inside the quoted ranges.
Worked examples with real numbers
All at 7% gradient and 500 m of ascent, 0.35 m² CdA, Crr 0.004, 97% efficiency:
| Rider + bike | Power | Climb time | Flat speed | Flat distance in that time | Flat m per m climbed |
|---|---|---|---|---|---|
| 70 kg | 250 W | 26 min 59 s | 36 km/h | 16.2 km | 32.4 |
| 80 kg | 250 W | 30 min 8 s | 35.8 km/h | 18 km | 36 |
| 90 kg | 250 W | 33 min 23 s | 35.6 km/h | 19.8 km | 39.6 |
| 80 kg | 200 W | 36 min 59 s | 33 km/h | 20.3 km | 40.7 |
| 80 kg | 300 W | 25 min 38 s | 38.3 km/h | 16.4 km | 32.7 |
The climb distance in the 80 kg case is 7,160 m of road, so the climb is also 7.2 km long. Heavier riders and lower power make the climb take longer, so more flat distance fits in the same time, while the flat speed itself barely depends on mass.
An energy view is different
If you count work rather than time, the gravity term alone is m g h. For 80 kg and 500 m that is 80 × 9.8 × 500 = 392,000 J (392 kJ) at the wheel, before rolling resistance and drag on the climb. The time-based equivalent above is the one to use for planning how long a ride will feel; an energy comparison depends on a different flat speed and gives a different ratio.
What this calculator leaves out
It assumes constant power, steady gradient and no wind. Real climbs vary, and riders cannot hold the same power for a short flat effort and a long climb. Pacing, heat, altitude and drafting are all outside the model.
Common mix-ups
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Often assumedEvery metre climbed equals a fixed number of flat metres, whoever you are.
What the source saysThe power equations have separate terms. Gravity is v m g s, rolling resistance is v m g Crr and air drag is half rho v cubed CdA, so the balance shifts with mass, speed and drag area. By our model, at 7% and 250 W the exchange is about 32 flat metres per metre climbed for a 70 kg rider and about 40 for a 90 kg rider. [1]
Checked against these sources on .
Frequently asked questions
Is there a standard equivalent between climbing and flat distance?
Not a universal one. This page uses equal time at equal power, which depends on your mass, power and the gradient. For 80 kg at 250 W on 7% it is about 36 flat metres per metre climbed.
Why does a lighter rider get a lower ratio?
A lighter rider climbs faster, so the climb takes less time and fewer flat kilometres fit in it. In our examples 70 kg gives about 32 and 90 kg about 40.
Does the gradient change the equivalent?
Yes. On a steeper slope you climb slower, but the same ascent is reached over a shorter road, so the time and the ratio change. Enter your climb’s average gradient.
Which equations does it use?
The power equations for gravity, rolling resistance and air drag from Wikipedia’s Bicycle performance article, solved for steady speed on the slope and on the flat.
Can I use it to compare two rides?
Yes, to compare how long they take at the same power. It is not a calorie or training-load comparison, because it matches time, not work.
Sources
Retrieved
- Wikipedia: Bicycle performance — the power equations and the quoted ranges for air density, rolling resistance and drivetrain losses (read 2026-10-26)
A model with a stated definition of equivalent
Not affiliated with Wikipedia. The article was read on 26 October 2026. The equivalent shown is our derived figure for equal time at equal power, not a published standard. Nothing you type is sent or stored.