Bike Frame Size Guide
Riding the right size frame is essential for comfort, efficiency and injury prevention. This guide provides height-to-frame-size tables for road, mountain and hybrid bikes, plus an introduction to stack and reach measurements for a more precise fit.
Road Bike Frame Sizes
| Rider Height | Frame Size (cm) | Frame Size (in) | Label |
|---|---|---|---|
| 152–160 cm (5'0″–5'3″) | 47–49 | 18.5–19.3 | XXS |
| 160–165 cm (5'3″–5'5″) | 49–51 | 19.3–20.1 | XS |
| 165–170 cm (5'5″–5'7″) | 51–53 | 20.1–20.9 | S |
| 170–175 cm (5'7″–5'9″) | 54–55 | 21.3–21.7 | M |
| 175–180 cm (5'9″–5'11″) | 56–57 | 22.0–22.4 | M/L |
| 180–185 cm (5'11″–6'1″) | 58–59 | 22.8–23.2 | L |
| 185–190 cm (6'1″–6'3″) | 60–62 | 23.6–24.4 | XL |
| 190–200 cm (6'3″–6'7″) | 62–64 | 24.4–25.2 | XXL |
Mountain Bike Frame Sizes
| Rider Height | Frame Size (cm) | Frame Size (in) | Label |
|---|---|---|---|
| 152–162 cm (5'0″–5'4″) | 33–37 | 13–14.5 | XS |
| 162–170 cm (5'4″–5'7″) | 38–42 | 15–16.5 | S |
| 170–178 cm (5'7″–5'10″) | 43–47 | 17–18.5 | M |
| 178–185 cm (5'10″–6'1″) | 48–52 | 19–20.5 | L |
| 185–198 cm (6'1″–6'6″) | 53–57 | 21–22.5 | XL |
Hybrid / Flat-Bar Bike Frame Sizes
| Rider Height | Frame Size (cm) | Label |
|---|---|---|
| 155–165 cm (5'1″–5'5″) | 43–47 | S |
| 165–175 cm (5'5″–5'9″) | 48–52 | M |
| 175–185 cm (5'9″–6'1″) | 53–57 | L |
| 185–198 cm (6'1″–6'6″) | 58–63 | XL |
Stack & Reach
Modern bike fitting increasingly uses stack (vertical distance from bottom bracket to top of head tube) and reach (horizontal distance) rather than seat tube length alone. These measurements better describe how a bike actually fits your body.
| Measurement | What It Affects | Guideline Range (road) |
|---|---|---|
| Stack | Handlebar height, upright vs. aero position | 510–620 mm |
| Reach | How stretched out you are, cockpit length | 370–410 mm |
A higher stack-to-reach ratio gives a more upright, comfortable position (endurance bikes: ~1.50+). A lower ratio is more aggressive and aerodynamic (race bikes: ~1.35–1.45).
Related Calculators
- Frame Size Calculator — enter your height and inside leg to get a personalised frame size recommendation
Frame sizes vary between manufacturers — a 56 cm from one brand may fit differently to a 56 cm from another. These tables are general guidelines. For the best fit, consider a professional bike fit or use detailed stack/reach comparisons. Leg length, arm length and torso proportions all affect ideal size.