Frame size charts are everywhere and most of them disagree. This calculator uses two standard methods — height, and inseam where you know it — and shows both. It gives you a starting point, not a fit.
The two methods, and why they disagree
Inseam × 0.65 gives a seat-tube length for a road frame. It is the older of the two methods and it is why a 175 cm rider with long legs gets told 56 cm while the same-height rider with short legs gets told 54 cm. Leg length matters more than total height.
Height alone is the fallback when you do not have a tape measure. It is less accurate by about one size in either direction, which is exactly the margin that makes a bike feel wrong.
Size chart by height
| Rider height | Road / gravel | Mountain bike | Kids’ wheel |
|---|---|---|---|
| 120–134 cm | — | — | 20″ |
| 135–149 cm | — | — | 24″ |
| 150–157 cm | 49–50 cm (XS) | S · 15–16″ | 26″ / 27.5″ |
| 158–164 cm | 51–52 cm (S) | S · 15–16″ | — |
| 165–171 cm | 53–54 cm (M) | M · 17–18″ | — |
| 172–178 cm | 54–56 cm (M) | M · 17–18″ | — |
| 179–185 cm | 56–58 cm (L) | L · 19″ | — |
| 186–192 cm | 58–60 cm (L–XL) | XL · 20–21″ | — |
| 193 cm + | 60–62 cm (XL) | XL · 21″ | — |
Three things the calculator cannot tell you
What actually determines fit
Three contact points do all the work: saddle height, saddle setback, and the distance from saddle to bars. Everything else — frame size, standover, wheel size — is a proxy for those three. If you already own a bike that fits, measure these three numbers and compare them to any new bike; it is far more reliable than a size chart.
How to measure inseam properly
- Stand against a wall, heels together, in the shoes you ride in.
- Put a spirit level or a hardback book between your legs, snug against the pubic bone — the same pressure a saddle would apply.
- Mark the top edge of the book on the wall and measure from the floor to that mark.
- Measure twice. A 1 cm error moves your frame size by most of a size.
Meihanda Bike Size Calculator, October 2026. Uses the inseam × 0.65 seat-tube convention for road and gravel, and standard height-based ranges for mountain and kids’ bikes. A starting point only — always check the specific model’s own size chart. Link: meihanda.com/bike-size-calculator
Related data
- China Bicycle Price Index — what each price band buys
- China Bicycle Cost Index — where the money sits
- OEM vs ODM vs open mould — tooling and MOQ
We publish frame geometry per model — ask for the size chart of the specific platform you are considering, in millimetres, before you commit to a size run. OEM & ODM terms · Start an inquiry · WhatsApp us
