calf size

Calf size refers to the circumference of the calf—the fleshy back portion of the leg between knee and ankle.

The term appears most often in contexts involving fitted clothing: These boots come in wide calf sizes, I need to measure my calf size for compression socks.

Calf size matters for boots, knee-high socks, and medical compression garments, where standard sizing often fails people with larger or smaller calves.