Saddle Height Calculator

How to use the calculator

1. Measure your inseam. Barefoot, back against a wall, feet about 6 in (15 cm) apart. Pull a hardcover book up between your legs, spine up and pressing the way a saddle would, and measure from the floor to the spine. Do it twice and take the average. Every 1 in of inseam error is almost 0.9 in of saddle height.
2. Pick your crank length. It is stamped on the inside of the crank arm (“170”, “172.5”, “175”). If you don’t know it, medium and large road bikes usually come with 172.5 mm cranks, and smalls with 170 mm.
3. To fine-tune, open More settings:
   • Sole + cleat: the stack between the bottom of your foot and the pedal axle. We take 15 mm as the baseline (road shoe with clipless pedal). If you ride flat pedals with thick-soled shoes or a taller setup, raise it.
   • Current saddle height: measured the same way as the recommended one. We tell you how much to raise or lower it.
4. Read the result and check it on the bike with the knee angle or the heel method (below).

Save to My Bike stores your inseam and crank length, and the other calculators use them without asking again.

Where to measure saddle height

Always the same way: from the center of the bottom bracket to the top of the saddle, along the line of the seat tube. Not straight up: the seat tube is angled (about 73° on a road bike), and measuring vertically gives you about 1 in (2-3 cm) less.

To measure at home, rest the end of a rigid tape measure on the center of the bottom bracket (the crank bolt) and run it along the seat tube to the middle of the saddle, where you sit. On saddles with a dipped center, lay a ruler across from side to side and measure to it.

How we calculate it

We use two classic methods and give you their average, because each one misses at one end:

LeMond method. Greg LeMond made it popular in his 1987 book, written with Kent Gordis:

Height = inseam × 0.883

It assumes 170 mm cranks, so we correct for yours: with 172.5 mm cranks we take off 2.5 mm; with 165 mm, we add 5 mm.

109% method (Hamley and Thomas, 1967). The first one to come out of a lab: the distance from the saddle to the pedal axle at the bottom should be 109% of your inseam. To turn it into a measurement from the bottom bracket, we subtract the crank:

Height = inseam × 1.09 − crank length

Recommended = the average of the two, plus the sole + cleat correction, with a ±1 cm (about ±3/8 in) range to fine-tune with your knee angle. For average inseams (31.5-34.6 in, 80-88 cm) the two methods nearly match. A study by Millour and colleagues found that 109% fits short inseams better and 0.885 fits long ones better; the average splits that error.

Example

A 32 in (81.3 cm) inseam and 172.5 mm cranks:

• LeMond: 32 × 0.883 − 0.1 = 28.2 in (71.5 cm)
• 109%: 32 × 1.09 − 6.8 = 28.1 in (71.3 cm)
• Recommended: 28.1 in (71.4 cm), range 27.7-28.5 in (70.4-72.4 cm)

Saddle height chart by inseam

Recommended height (average of the two methods) from the center of the bottom bracket to the top of the saddle, with the baseline sole and cleat:

For your exact measurement, see the full saddle height chart by inseam: it covers inseams from 27.5 to 37.4 in (70-95 cm), with 165 to 175 mm cranks and both methods side by side. If you are replacing your seatpost, check its diameter first.

Knee angle: the check that matters most

The formulas are a starting point. What really matters is how much your knee bends with the pedal at the bottom, and that also depends on your foot length, how you drop your heel and your flexibility.

• Reference range: 25-35° of knee flexion, measured static, seated, with the crank in line with the seat tube. Holmes, Pruitt and Whalen proposed it in 1994 to prevent overuse injuries, and nearly everyone uses it. The review by Bini, Hume and Croft (2011) recommends staying at 25-30° to lower the risk of knee injury.
• Watch out with 109%: in the Peveler and Green study (2011) of trained cyclists, the 109% height fell outside that range in 73% of cases. At 25° of knee bend, they also used less oxygen than at 109%.
• Your knee opens up more while pedaling: about 8° more than the static measurement (Millour, 2019). That is why fitters who work from video look for 33-43° in motion. Ferrer-Roca (2012) found that more than half of well-trained cyclists had their saddle outside 106-109% of their inseam.

To measure it at home, have someone take a side-on photo of you with the pedal at the bottom and measure the angle between your thigh and lower leg with a goniometer app. A fully straight leg is 0°.

The heel method

The classic quick check: seated on the saddle, put your heel on the pedal at the bottom of the stroke. Your leg should be straight, without your hips tipping to the side. When you pedal with the ball of your foot, your knee will be slightly bent, roughly in the right range.

It keeps you from being way off, but it is not precise: it depends on your foot length and how you drop your heel. Use it to confirm the calculator has not strayed from what is reasonable.

Common mistakes

• Measuring your inseam without pressing the book up. It comes out about 1 in (2-3 cm) short and your saddle ends up low. The book has to press as hard as the saddle does.
• Measuring the height vertically instead of along the seat tube.
• Copying the height from another bike without checking the cranks. If one has 175 mm cranks and the other 170 mm, the saddle changes by 5 mm.
• Forgetting new cleats or shoes. Thinner new soles drop your foot relative to the pedal: adjust the saddle to match.
• Riding with the saddle low “to touch the ground.” You don’t need to reach the ground with your feet while seated: when you stop, you slide forward off the saddle. A low saddle loads the front of the knee.
• Changing it by 3/4 in (2 cm) all at once. Go in 5 mm steps.

If something hurts

• Pain at the front of the knee (kneecap): usually a saddle that is too low or too far forward.
• Pain behind the knee or in the hamstrings: usually a saddle that is too high.
• Pain on the outside of the knee: can be height, but also cleat position.

If the pain continues after adjusting, see a physical therapist or a professional bike fitter. To pick the right bike before adjusting anything, use the bike size calculator, and if you are unsure about cranks, the crank length calculator.

Updated October 19, 2026 ·Report an error on this page