Bike fit and geometry
Frame size, saddle, bars, stem and cleats.
- Bike Frame Size CalculatorFrame size is an inseam problem first. Road multiplies inseam by 0.665, gravel by 0.655, MTB by 0.574, then nudges a centimetre if your torso is unusually long or short for that inseam.
- Stack and Reach Ratio CalculatorStack over reach is the quickest way to see if a frame wants your hands low. The ratio ignores stem and spacers, so it compares frames rather than a finished bike.
- Optimal Saddle Height CalculatorThe LeMond method is a measured starting saddle height, not a knee-angle fit. Multiply inseam in millimetres by 0.883, then fine-tune so the knee is slightly bent at the bottom of the stroke.
- Handlebar Width CalculatorMeasure acromion to acromion — the bony tips of the shoulders — and use that as the road hood-to-hood width. Gravel adds 20 mm for control off-road. A flat MTB bar is measured end to end, so it comes out far wider: about 1.9 times the shoulder width.
- Crank Length CalculatorCrank length follows inseam in 4 cm bands. The second number is 2.5 mm shorter — the length many fitters try when hip angle or cadence feels cramped.
- Stem Length and Angle CalculatorA stem is a hypotenuse, but its angle is quoted square to the steerer, not to the ground. On a 73° head tube a −17° stem sits level and a −6° stem still climbs 11°. Length and that real tilt split into horizontal reach and vertical rise.
- Cleat Fore-Aft CalculatorThe cleat centre wants to sit under the first and fifth metatarsal heads. From EU size this estimates foot length, then marks 35% of that length back from the toe.