Last updated October 10, 2026 · Report an error
Body frame size — small, medium, or large — affects what a healthy weight range looks like for a given height, beyond what BMI alone captures.
This calculator estimates your frame size using the well-established height-to-wrist-circumference ratio method.
How it works
Enter your height, wrist circumference, and sex. The calculator divides height by wrist circumference and compares the result against published thresholds (which differ slightly between men and women) to classify your frame size.
- Enter height (cm).
- Enter wrist circumference (cm).
- Enter sex.
- Click Calculate to see your results.
Examples
170 cm height, 16 cm wrist, male
A 170 cm tall man with a 16 cm wrist has a height-to-wrist ratio of 10.625, which falls in the small frame category (ratio above 10.4 for men).
Who should use it
- Adding context to a healthy weight range beyond BMI or the Ideal Body Weight Calculator alone.
- General curiosity about bone structure and body frame classification.
Industry applications
- Fitness and personal training
- Health and nutrition coaching
Advantages
- Uses the same wrist-to-height ratio method found in established height-weight reference tables.
- Simple, quick 2-measurement calculation.
Limitations
- A simplified frame-size estimate, not a comprehensive body composition or somatotype analysis.
Common mistakes to avoid
- Measuring the wrist at the wider point near the hand rather than at the actual wrist bone.
- Pulling the tape measure too tight, which understates the true wrist circumference.
Best practices
- Measure your wrist with a soft tape measure snug against the skin, not compressed, for the most accurate ratio.
Tips
- Pair this with the Ideal Body Weight Calculator — a larger frame size generally supports a somewhat higher healthy weight within the same height.
Frequently asked questions
Yes, with no signup and no limit on how many calculations you run.
Measure around the wrist bone (the narrowest point of the wrist, just below the hand) with a flexible tape measure, without pulling it tight.
Two people with the same height and BMI can have very different bone structures — frame size adds context to weight and body composition assessments, since a larger frame naturally carries more bone and muscle mass.
Not exactly — this calculator uses the standard clinical frame-size method (small/medium/large) based on bone structure, rather than the more subjective ectomorph/mesomorph/endomorph body-type classification system.