Body Frame Size (Wrist) Calculator
Determine whether you have a small, medium or large body frame from your height-to-wrist ratio — the standard way to personalise ideal-weight ranges.
How it works
r = height(cm) ÷ wrist circumference(cm) · Male: r>10.4 small, 9.6–10.4 medium, <9.6 large · Female: r>11.0 small, 10.1–11.0 medium, <10.1 large
Frame size captures how heavy your skeleton is, which shifts a “healthy weight” range up or down. The wrist has almost no fat or muscle, so its circumference relative to your height is a reliable proxy for bone size. A large frame carries more weight for the same height without excess fat, while a small frame carries less.
Worked example
A man 178 cm tall with a 17.5 cm wrist has a ratio of 178 ÷ 17.5 = 10.17. That is between 9.6 and 10.4, so he has a medium frame — the standard reference against which his ideal-weight range should be set.
Frequently asked questions
Where exactly do I measure the wrist?
Wrap a tape just above the wrist bone (toward the hand), at the narrowest point, snug but not tight. Measure your dominant hand for consistency.
Why does frame size matter?
People with larger frames have heavier bones and broader joints, so their healthy weight is a few kilograms higher than a small-framed person of the same height. Ideal-weight formulas use frame size to widen or narrow the target range.
Is the wrist method accurate?
It is a quick, well-established estimate, but it is only an approximation of skeletal size. Elbow-breadth measurement is slightly more precise; for body composition, pair frame size with a body-fat estimate.
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Educational estimate only — not medical advice, diagnosis or treatment. Consult a qualified clinician for health decisions.