Body Frame Size Calculator
Estimate whether your skeletal frame is small, medium or large from your height and wrist circumference using the height-to-wrist ratio method.
What body frame size means
Body frame size describes your underlying skeletal build — usually grouped as small, medium or large. It is not a measure of body fat or fitness, but it can add context when interpreting ideal-weight and BMI ranges.
How the wrist ratio works
Divide standing height by wrist circumference using the same unit for both. For men, a ratio above 10.4 is small, 9.6–10.4 is medium, and below 9.6 is large. For women, above 11.0 is small, 10.1–11.0 is medium, and below 10.1 is large.
Worked example
A man who is 70 in tall with a 7 in wrist has a ratio of 70 ÷ 7 = 10.0, which falls in the medium-frame band.
Frame-size thresholds
| Sex | Small | Medium | Large |
|---|---|---|---|
| Men | > 10.4 | 9.6–10.4 | < 9.6 |
| Women | > 11.0 | 10.1–11.0 | < 10.1 |
Frequently asked questions
How do I find my body frame size?
- Divide your height by your wrist circumference and compare the ratio with the sex-specific small, medium and large bands.
Why does frame size matter?
- It adds context to height-based ideal-weight ranges because people of the same height can have different skeletal builds.
Where should I measure my wrist?
- At the narrowest point just above the wrist bone, with the tape snug but not tight.
Is frame size the same as body fat?
- No. Frame size describes skeletal proportions, not fat mass or body composition.
Disclaimer. Frame size is a rough anthropometric estimate, not a measurement of bone density, body fat or health.