{"id":11053,"date":"2026-02-08T21:54:29","date_gmt":"2026-02-08T20:54:29","guid":{"rendered":"https:\/\/www.athletesonthemat.com\/?post_type=product&p=11053"},"modified":"2026-08-20T23:22:19","modified_gmt":"2026-08-20T21:22:19","slug":"brazilian-jiu-jitsu-belt-kosen","status":"publish","type":"product","link":"https:\/\/www.athletesonthemat.com\/en\/brazilian-jiu-jitsu-belt-kosen\/","title":{"rendered":"Brazilian Jiu-Jitsu Belt, Kosen"},"content":{"rendered":"

Brazilian jiu-jitsu belt<\/strong> KOSEN, available from white to black. Tightly woven cotton, a reinforced rank bar, gold embroidery on the visible end. A belt built to survive several years of training, not to look good on promotion day.<\/p>\n

Specifications<\/h2>
Weave<\/dt>
Coton<\/dd>
Stitching<\/dt>
8 rows of stitching<\/dd>
Approval<\/dt>
IBJJF<\/dd>
Available sizes<\/dt>
A0, A1, A2, A3, A4<\/dd>
Manufacturing<\/dt>
Made in Pakistan<\/dd>
Weight in A2<\/dt>
0.250 kg<\/dd><\/dl><\/div>\n

Meets IBJJF rules<\/h2>\n

The IBJJF rulebook is specific about belts. Width between 4 and 5 cm, a black rank bar up to brown belt, red or white for black belts, and enough length that each end hangs 20 to 30 cm once the knot is tied.<\/p>\n

The KOSEN meets all three. Just pick the right length: it is the one criterion on which a uniform check can turn away an otherwise perfectly legal belt.<\/p>\n

Getting the length right<\/h2>\n

A belt that is too short comes undone on the first guard pass. One that is too long drags on the mat and gets in the way. The rule is simple: after two wraps and the knot, 20 to 30 cm should remain on each side.<\/p>\n

Sizes run from A1 to A5 based on waist measurement, not on your gi size. A lean athlete in an A3 gi may well wear an A2 belt. Use the chart below, it gives the actual lengths.<\/p>\n

The embroidery<\/h2>\n

The gold section is written in katakana: \u30d5\u30a1\u30a4\u30bf\u30fc reads fait\u0101<\/em>, the Japanese transcription of the English word fighter<\/em>. It is not decorative calligraphy picked at random, it is a readable word, written in the syllabary Japanese reserves for foreign terms.<\/p>\n

Should you wash your belt?<\/h2>\n

Tradition says no, that a belt absorbs its owner’s experience and that washing it would erase the work behind it. It is a good story, and it is a recent one, spread largely by social media.<\/p>\n

Reality is simpler. A belt spends every session in contact with your gi, the mats and your training partners. It collects exactly the same bacteria and fungi as the rest of your kit. Jiu-jitsu skin infections, ringworm and impetigo first among them, make no exception for folklore.<\/p>\n

Wash it. At 30 \u00b0C, with your gi, no fabric softener, line dry. A black belt will lose a little depth over the years, a white belt will stay white, and nobody on the mat will hold it against you.<\/p>\n

One belt per rank, or one for life?<\/h2>\n

Every promotion calls for a new belt. Plenty of people keep the old ones. It is the only object in this sport that tells the story of a progression. If you are starting out, buy a white one and do not get ahead of yourself: rank is awarded, not purchased.<\/p>\n

FAQ<\/h2>\n

Is the rank bar stitched or glued?<\/h3>\n

Stitched, along its full height. That is the area that takes the degree stripes, so it has to survive repeated pulling and needles.<\/p>\n

Does the belt shrink in the wash?<\/h3>\n

Slightly, like any cotton, and mostly on the first wash. Allow for that: between two lengths, take the longer one.<\/p>\n

Can I use it at IBJJF events?<\/h3>\n

Yes, subject to the length check described above, and provided the colour matches your rank.<\/p>\n

Does it work for judo or karate?<\/h3>\n

Physically yes, but ranking conventions differ between arts. This belt is made for Brazilian jiu-jitsu and its rank bar follows BJJ conventions.<\/p>\n

\r\n

Related guides<\/h2>\r\n
Size guide<\/b>Measurements, in-between sizes<\/a>\r\nFabric weight and weave<\/b>GSM, pearl weave, ripstop<\/a>\r\nIBJJF rules<\/b>Colours, measurements, patches<\/a><\/div>\r\n<\/div>\n","protected":false},"excerpt":{"rendered":"

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