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Free fit tool

Bike Size
Calculator.

Enter your height and inseam and pick your bike type to get the frame size and S, M or L that fits you best.

Your measurements
Height
ft
in
Recommended frame
56 cm
Size Large
Suggested range 55 to 57 cm
A starting recommendation. Standover clearance and reach vary by brand, so use it to shortlist sizes, then test ride before you buy.

Results update as you type. Frame geometry differs between brands; always check the maker's own size chart and standover height.

The method

How the calculator works

Frame size follows your inseam and the bike type. Each type has its own multiplier and its own unit.

in
Inseam first Leg length sets standover and saddle height, so inseam is the strongest signal. Enter it for the most accurate result.
h
Height fallback No inseam to hand? The tool estimates it from your height so you still get a solid recommendation.
x
Type multiplier Road uses inseam x 0.665 in cm, mountain uses inseam x 0.226 in inches, hybrids sit a little higher. The tool picks the right one.
S
S / M / L label Alongside the number you get a size label, because many bikes are sold as Small, Medium and Large.
~
Range not a point Two riders the same height can prefer different frames, so a range is shown. Pick smaller for agility, larger for comfort.

Use the result to shortlist sizes, then confirm on the bike. Check you can stand over the top tube with a little clearance, and that the reach to the bars feels comfortable rather than cramped or stretched.

Want a printable bike fit cheat sheet?
A one-page sizing and saddle-height reference is coming soon to our shop.
FAQ

Bike size FAQ

As a guide, a 178cm (5ft 10in) rider suits a 56cm road frame or a 19in mountain frame, while a 168cm rider suits about 53cm road. Frame sizing varies by bike type, so enter your height and pick the type above for a recommendation tuned to you.

Inseam is more accurate because leg length drives standover and saddle height more than total height does. If you know your inseam, enter it and the calculator uses it directly. If you leave it blank, it estimates inseam from your height.

Sizing between two frames is common. Choose the smaller size for a sportier, more agile fit and easier standover, or the larger size for a more relaxed, stretched-out position. Reach and saddle height can be fine tuned with stem length and seatpost, so a test ride is the best tiebreaker.

Stand with your back to a wall in socks, feet about 15cm apart, and pull a book up firmly between your legs like a saddle. Measure from the top of the book to the floor. That distance in centimetres is your cycling inseam.

Yes. Road, gravel and city frames are usually measured in centimetres of seat tube, while mountain bikes are often given in inches or as S, M and L. The same rider needs different numbers on each, which is why this tool switches units and labels with the bike type.

A little off is manageable with fit tweaks, but a long way off is not. Too big and you cannot stand over the top tube or reach comfortably; too small and the bike feels cramped and twitchy. Get within the recommended range, then dial in saddle height, setback and stem length.