Body Type Calculator · Practical guide
Wrist-to-Height Ratio Body Type Test
One wrist measurement divided by your height classifies your frame as ectomorph, mesomorph, or endomorph.
At a glance
How the Test Works
Measure your wrist circumference at its narrowest point, just below the wrist bone, and divide it by your height — both in centimeters. The result is your wrist-to-height ratio, a proxy for bone frame size: smaller wrists relative to height mean a lighter frame (ectomorph), and larger wrists a heavier frame (endomorph).
Interactive tool
Body Type Calculator
Enter your own values, then compare the result with the examples below.
Results
The Exact Cutoffs
| Body Type | Men | Women |
|---|---|---|
| Ectomorph | below 0.1045 | below 0.1045 |
| Mesomorph | 0.1045 to 0.1225 | 0.1045 to 0.1195 |
| Endomorph | above 0.1225 | above 0.1195 |
Women's mesomorph band is slightly narrower because average wrist size differs less with height in women. These are the thresholds the calculator applies.
Worked Examples
A woman with a 16 cm wrist at 165 cm tall: 16 ÷ 165 = 0.0970 — ectomorph. At an 18 cm wrist she would measure 0.1091 — mesomorph. At a 20 cm wrist, 0.1212 — endomorph. Notice that a 2 cm difference in wrist size can move the classification, so measure carefully.
How to Measure Your Wrist Correctly
Use a flexible tape or a strip of paper marked against a ruler. Wrap it around your wrist just below the bony bump (the styloid process), snug but not tight, with your hand relaxed and open. Measure to the nearest millimeter or sixteenth of an inch — and convert inches to centimeters (multiply by 2.54) before dividing, since the calculator works in metric.
What the Ratio Does Not Tell You
Frame size is fixed, but body composition is not. The ratio says nothing about your current fat or muscle — it only describes the skeleton underneath. Pair it with the four-question quiz in the calculator, which captures how you actually gain muscle and fat, for the fullest picture.
Frequently Asked Questions
Which wrist should I measure?
Measure your non-dominant wrist — it is usually slightly smaller and less influenced by muscle use. If the two differ noticeably, use the smaller measurement.
Can I use inches instead of centimeters?
The ratio works in any unit as long as wrist and height use the same one, because the units cancel. Just be consistent: divide wrist in inches by height in inches, or centimeters by centimeters.
Why does wrist size indicate body type?
The wrist carries almost no muscle or fat, so its circumference closely reflects bone thickness — and bone frame size is the stable structural difference behind the three somatotypes.
What if my ratio lands exactly on a cutoff?
You are a borderline blend, which is common. Read the descriptions for both adjacent types and use the quiz to see which training and nutrition advice fits your experience better.