Elbow Breadth Frame Size Calculator

How it is calculated

The tool divides elbow breadth by height and expresses it as a percentage: elbow index % = elbow breadth ÷ height × 100, both in centimetres. That percentage is compared with fixed bands by sex. For men, below 3.6 % is a small frame, 3.6 % to 4.0 % medium and above 4.0 % large. For women, below 3.4 % is small, 3.4 % to 3.8 % medium and above 3.8 % large. The boundary values themselves fall into the medium band. Anything other than female is treated as male. Height outside 50–272 cm or elbow breadth outside 3–15 cm shows no result. The bands are a rule of thumb for adults, so treat the category as a rough guide.

Common mistakes

• Entering the elbow circumference instead of the breadth. Breadth is the bone-to-bone width across the joint, measured with a caliper, and is far smaller.
• Entering millimetres or inches. The elbow field expects centimetres, and a value outside 3–15 cm shows no result.
• Measuring with the arm hanging straight and the soft tissue squeezed, rather than bent at 90 degrees across the two bony points.
• Choosing the wrong sex. An index of 3.89 % is a medium frame on the male scale but a large frame on the female scale.
• Treating the category as a verdict. A man at 7.2 cm and 180 cm lands exactly on 4.00 % and counts as medium, while 7.3 cm would be large, so small measuring errors can change the band.