Is your gearing low enough for your climbs?
Enter rider, route and drivetrain to see whether your easiest gear is enough and which setup fits better.
Your gears
How to read the chart
Each dot is a gear, placed by its speed at rpm. The green line is your speed on the steepest section, which only depends on power, weight and gradient. With every gear left of the line you climb at least at this cadence, to the right of it you have to pedal slower.
Setups that work
How mybikesetup calculates
Climbing power goes into three resistances: gravity, rolling resistance and air drag. The calculator solves for the speed at which your power is exactly enough:
P · η = m · g · (sin θ + Crr · cos θ) · v + ½ · ρ · CdA · v³
Power is assumed constant over the whole climb. Speed on the steepest section determines cadence, speed at the average gradient determines duration. Speed, wheel circumference and cadence give the gear ratio. Assumptions: rolling resistance 0.004 on road, 0.008 on gravel and 0.012 on MTB, CdA 0.40, 0.42 and 0.50 m², drivetrain efficiency 97 %, air density 1.2 kg/m³. Easy equals 60 % and steady 75 % of FTP, and the share can be set freely. All out uses the power you can roughly sustain for the duration of the climb, estimated as FTP × (duration / 60 min) to the power of −0.07. This is a rough guide and varies a lot between riders. Without FTP the calculator assumes 2.0, 2.8 or 3.5 watts per kilogram.
Derailleur capacity = (largest minus smallest chainring) + (largest minus smallest cog). It is checked against capacity, largest cog and maximum chainring difference as specified by the manufacturer. Freehub, chain and shifter compatibility are not checked.
Sources: Shimano specifications, SRAM RED XG-1290, SRAM FC-RED-E1, SRAM XG-1371, Campagnolo Super Record 13, Super Record X, Ekar. Older 10 and 11-speed SRAM cassettes come from the SRAM model pages. Individual cogs of current SRAM AXS cassettes and Campagnolo 11 and 12-speed come from dealer data sheets and are marked as such. As of October 2026.
Results are a guide. Check with the manufacturer or your bike shop before buying.
The right gearing for climbs
Whether your easiest gear is low enough depends on three things: your power, your weight including the bike, and the gradient of the steepest section. Together they set your speed. With wheel circumference and the cadence you still want to pedal, that gives the gear ratio you need at least.
The gear ratio is teeth at the front divided by teeth at the rear. 34/34 gives 1.0, smaller values are easier. The calculator compares your easiest gear with what you need and suggests setups that have a matching rear derailleur.
Chart by gradient and power in the guide Gearing for climbs →
Common questions
What gear ratio do I need for a 10% climb?
It depends on power and weight. At 84 kg total and 200 watts you ride about 8.1 km/h on a road bike. To pedal at least 80 rpm you need a ratio of 0.79. With 250 watts 0.98 is enough. For comparison: 34/34 is 1.0.
What does a gear ratio of 1.0 mean?
One crank turn turns the rear wheel exactly once, for example with 34 teeth at the front and 34 at the rear. With 28 mm tires on 700C you cover about 2.13 m. Smaller values are easier.
Smaller chainring or bigger cog?
For the easiest gear only the ratio counts. 32/32 is as easy as 34/34. They differ in the hardest gear, the gaps between gears and whether the derailleur can handle a bigger cassette.
Will a bigger cassette fit my derailleur?
Not always. Every derailleur has a largest cog and a capacity, meaning how much chain it can take up. The calculator checks both and only suggests setups with a matching derailleur. It does not check freehub, chain or shifters.
What cadence on climbs?
That is personal. You set your minimum cadence in the calculator, 80 rpm by default. The lower it is, the harder your easiest gear may be.