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Saddle height calculator

Your inseam and your crank length decide where the saddle starts. Enter both and you get a range to set up from, not a single number pretending to be exact.

Enter your inseam to see a starting height. Stand barefoot with your feet 15–20 cm apart, press a thick book up between your legs like a saddle, and measure from the floor to the top of the book.

Open Bike Fit

The full tool checks a real bike against your measurements.

Why a range and not one number

The LeMond method multiplies your inseam by 0.883, but the factor riders actually settle on spans roughly 0.873 to 0.893 — about 16 mm apart for an 80 cm inseam. Anyone quoting a single millimetre is hiding that spread. Set the saddle in the middle of the range, ride it, and move in steps of 5 mm.

Crank length changes the answer

Saddle height is measured to the bottom bracket, but your leg extends to the pedal. Fit 165 mm cranks instead of 172.5 mm and the pedal sits 7.5 mm closer at the bottom of the stroke, so the saddle goes up by about the same amount to keep the same leg extension. The calculator does that correction for you.

Measure the inseam properly

Stand barefoot with your back to a wall and your feet 15–20 cm apart. Press a thick hardback book up between your legs, spine horizontal, firmly enough to mimic a saddle. Mark the top of the spine on the wall and measure to the floor. Measure three times and take the middle value — a centimetre of error here is about 9 mm of saddle height.

Then check it on the bike

Formulas can only see a tape measure. Fitters check the knee angle at the bottom of the pedal stroke, which lands between 25° and 35° for most riders, and watch whether the hips rock. If your hips rock side to side, or you feel pain behind the knee (often too high) or in front (often too low), trust the bike over the formula.

Check a whole bike, not one numberBike Fit takes your measurements and a geometry chart and gives the full starting setup — plus what to adjust.

How to set your saddle height

Saddle height is the fit change with the largest effect and the easiest to measure: from the centre of the bottom bracket to the top of the saddle, along the seat tube. The LeMond method — inseam × 0.883 — has been the standard starting point since the 1980s because it is quick, repeatable, and close enough to ride from.

This calculator shows the answer as a range, corrects it for your crank length, and hands the number to the full Bike Fit tool, which adds saddle setback, stem length and spacers for a specific bike.

Frequently asked questions

How do I calculate saddle height from inseam?+

Multiply your inseam in millimetres by 0.883 (the LeMond method). That gives the distance from the centre of the bottom bracket to the top of the saddle, measured along the seat tube. For an 810 mm inseam that is about 715 mm. Riders settle anywhere between 0.873 and 0.893 of inseam, so treat it as a range and fine-tune by feel.

Does crank length change saddle height?+

Yes. Shorter cranks put the pedal closer to the bottom bracket at the bottom of the stroke, so the saddle goes up by roughly the difference to keep the same leg extension. Moving from 172.5 mm to 165 mm cranks raises the saddle about 7.5 mm.

What knee angle should I have at the bottom of the pedal stroke?+

Most fitters aim for 25–35° of knee bend at the bottom of the stroke with the foot level (the Holmes method). Towards 25° favours power, towards 35° is easier on the knee. A formula cannot see this, so check it on the bike once the saddle is roughly set.

Is my saddle too high or too low?+

Hips rocking side to side on the saddle, toes pointing down to reach the bottom of the stroke, or pain behind the knee usually mean too high. Pain at the front of the knee, or feeling cramped at the top of the stroke, usually means too low. Change 5 mm at a time and ride a few times before the next change.

Is this the same as the full bike fit?+

No — it answers one number. Bike Fit also checks standover, seatpost, saddle setback and where your hands land on a specific frame, and tells you which stem and spacers get you there.

Related reading

Bike Fit: check a whole bikeStem length calculatorStack and reach calculatorGuide: frame size, saddle height & stem