Gear & Sizing

BJJ Belt Size Calculator

Find your BJJ belt size. Belts run on the same A0–A5 scale as gis — this gives you a starting size from your height, to confirm against the maker's chart.

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How belt sizing works

BJJ belts are sold on the A-size scale (A0 through A5) that mirrors gi sizing, and the right belt is the one that matches your gi size — not strictly your height. Height is the best single predictor when you don't yet know your gi size, which is what this tool uses, but if you already own a gi, order the belt in the same A-size.

There's no universal standard between brands, so treat the result as a starting point and check it against the manufacturer's chart before buying.

Getting the length right

A correctly sized belt wraps your waist twice and finishes with two even tails of roughly 20–25 cm (8–10 in) after the knot. Too long and the tails dangle and get stepped on; too short and the knot won't hold. If you're between sizes, size down for a snugger tie unless you're carrying more around the waist, in which case size up.

Frequently asked questions

What size BJJ belt do I need?
Order the belt in the same A-size as your gi. If you don't know your gi size yet, this tool gives a height-based starting point — then confirm against the brand's chart.
Do belts shrink?
Cotton belts can shrink slightly in a hot wash and dry, like a gi. If you're between sizes and wash warm, the longer option is the safer pick.
Are belt sizes the same across brands?
Roughly, but not exactly — each brand cuts its own lengths. Always check the specific maker's size chart, especially for the smallest and largest sizes.