Saddle Height Calculator (Free)
Enter your inseam to see both formula results here.
The formula result is a starting point, not an endpoint. It uses inseam alone — blind to your flexibility, crank length and cleat position — and the two formulas often differ by 5–15mm for the same rider. After setting the initial height, film a side-view riding video and calibrate the BDC knee angle (endurance 140–150°, performance 135–145°).
Don't want to screenshot and measure the angle yourself?
Upload a side-view riding video and Bikefit.AI measures your actual BDC knee angle, hip angle and torso angle, and tells you whether to raise or lower the saddle and by how much — turning the formula's "start" into a calibrated "finish".
Upload a video — calibrate precisely ›What the two formulas are
LeMond method (0.883 × inseam): distance from the BB center along the seat tube to the saddle top; the most popular on road bikes. Hamley 109% method (1.09 × inseam): measured from the pedal surface (crank in line with the seat tube) to the saddle top. They use different references, so the raw numbers aren't directly comparable — both are starting points. To understand why they drift and how to calibrate with the knee angle, see Four saddle-height methods compared.
How to measure inseam
Stand barefoot against a wall, feet about pedal-stance width apart, and pull a hardcover book firmly up into your crotch (simulating saddle pressure) with the spine level. Measure from the top of the spine to the floor, three readings averaged to within ±3mm — a 1cm inseam error shifts the calculated saddle height by ~9mm.
FAQ
Can I use the value directly?
As a start only. Calibrate with the measured knee angle afterward; don't lock it in.
The two results differ — which one?
Different references, equally approximate. Pick either start; the knee-angle calibration is what matters.
My knee already hurts — now what?
Read Knee pain & saddle height for direction; persistent pain means see a doctor.
Related: Four saddle-height methods · Knee pain & saddle height · All guides