Body frame size
Small, medium or large — from your wrist and your height. A descriptive label, not a health measure.
Measure around the wrist just past the wrist bone (toward the hand), where it’s narrowest. Snug, not tight.
Unlike every other calculator on WIMSTA, these frame thresholds have no reproducible, peer-reviewed origin. They circulate across health sites almost unchanged since the mid-20th century and trace back to Metropolitan Life insurance-era height–weight tables — not to a validated study we can cite, with a sample and a published error. There is no primary source, and we won’t pretend one exists. We show the method anyway, labelled plainly, because a wrist and a tape measure are something you can actually check at home and the question is widely asked — the same reason we keep “220 − age” visible on the method page. The one frame measure that does have a real peer-reviewed source is elbow breadth (Frisancho, Am J Clin Nutr 1984) — but it needs calipers, not a tape, so we name it rather than build it.
What your frame is not
Frame size is a descriptive category, nothing more. It says nothing about your health, your body fat, or your fitness, and WIMSTA does not use it to adjust an “ideal weight” — ideal-weight-as-a-target isn’t something we calculate at all. Historically, frame size was used to explain away a “normal” weight; treat your result as a note about your skeleton, not a judgement of your body.
How to measure your wrist
- Use a flexible tape measure, not a rigid ruler.
- Wrap it around the wrist of your dominant hand, just past the wrist bone toward the hand — at the narrowest point.
- Keep it snug against the skin but not tight.
- Read the number where the tape meets, and enter it above.
Want something you can actually trust?
Frame size is folklore with a tape measure. For signals that rest on verifiable, peer-reviewed sources, two are worth more of your attention:
Frequently asked
How is body frame size calculated?
This calculator divides your height by your wrist circumference (both in centimetres). A higher ratio — a thin wrist for your height — reads as a smaller frame; a lower ratio reads as larger. The exact cut-offs differ by sex.
Is the frame size formula scientifically validated?
No. The wrist-ratio thresholds have no reproducible, peer-reviewed primary source — they trace to mid-20th-century Metropolitan Life tables and circulate unchanged across the web. We show the method openly labelled rather than dressed up as science. The one frame measure with a real source is elbow breadth (Frisancho, 1984), which needs calipers.
Does my frame size mean I’m overweight or underweight?
No. Frame size is a descriptive skeletal category. It says nothing about your weight, your body fat, or your health, and we do not use it to adjust any “ideal weight.” If you want a health-relevant number, use waist-to-height ratio or a body-fat estimate.
Where do I measure my wrist for frame size?
Wrap a tape measure around your wrist just past the wrist bone toward the hand, at the narrowest point — snug but not tight.
Which is more reliable, wrist or elbow measurement?
Elbow breadth (Frisancho, NHANES, 1984) has the real peer-reviewed pedigree, but it requires sliding calipers, so almost no one can do it at home. Wrist circumference is measurable with a tape but has no validated source. Neither is a health metric.