Body Frame Size Calculator
Determine if you have a small, medium, or large body frame using wrist circumference and height measurements
Your Measurements
Measure around wrist just below the wrist bone (at the narrowest point)
How It Works
Height-to-Wrist Ratio Method
This method uses the ratio of your height to your wrist circumference. Wrist size is a reliable indicator of skeletal structure because it's mostly bone with minimal fat or muscle.
- Small frame: r > 10.4
- Medium frame: 9.6 ≤ r ≤ 10.4
- Large frame: r < 9.6
- Small frame: r > 11.0
- Medium frame: 10.1 ≤ r ≤ 11.0
- Large frame: r < 10.1
Example Calculation
Example: Male, 175 cm tall, wrist circumference 17 cm
Step 1: Calculate ratio: r = 175 / 17 = 10.29
Step 2: Compare to thresholds:
• 10.29 falls between 9.6 and 10.4
Result: Medium Frame
Interpretation: Average skeletal structure with moderate bone density
Frequently Asked Questions
What is body frame size? ▼
Body frame size refers to your skeletal structure - the mass and density of your bones. People with larger frames naturally weigh more than those with smaller frames at the same height and body fat percentage.
Why measure the wrist? ▼
The wrist is an ideal measurement point because it consists primarily of bone with minimal muscle or fat. This makes it a reliable indicator of overall skeletal structure. Other methods use elbow breadth for the same reason.
How does frame size affect ideal weight? ▼
Large-framed individuals have heavier bones and can carry 10% more weight than small-framed people of the same height. Frame size should be considered when setting weight goals alongside BMI and body composition.
Can I change my frame size? ▼
No, frame size is determined by genetics and skeletal structure. While you can build muscle and lose fat, your underlying bone structure remains constant. However, resistance training can increase bone density.
Is frame size the same as body type (ectomorph, etc.)? ▼
No. Frame size refers specifically to skeletal structure. Body type (somatotype) describes overall physique including muscle and fat distribution patterns. An ectomorph typically has a small frame, but not always.
References & Sources
Comprehensive guide to body frame size calculation methods
Medical overview of frame size and its health implications
Guidelines on using frame size with BMI for weight assessment
Overview of skeletal frame measurement methods