How to Choose a BJJ Rash Guard: 5 Criteria

The essentials in 30 seconds

1. The fit: close to the body, long enough

In BJJ, the rash guard works on the mat: it slides, gets pulled, and rides up during sweeps and transitions. 3 details make the difference.

• The fit: it should stick like a 2nd skin. If it folds at the stomach, it will ride up and give your opponent something to grab.
• Body length: it should cover the torso down to the shorts' waistband, and a bit beyond. That's also an IBJJF rule requirement.
• The shoulders: with 4-way stretch fabric, you can raise your arms, pull a high guard, or bridge without the hem riding up.

Men's and women's cuts aren't the same: the women's cut is fitted at the chest and hips. See the women's rash guards and the men's rash guards.

2. The fabric: weight, material, seams

At Rashu, rash guards are 84% polyester and 16% elastane, 230 g/m², with flat seams. In short: a fabric dense enough not to turn see-through when stretched across the back, flexible enough to follow a high guard.

3. The print: into the fiber or a transfer

This is the point most buyers overlook, and the one that decides how long the design lasts.

• Print in the fiber: the ink turns to gas and enters the polyester fiber before the seams are sewn. The design becomes part of the fabric: it stretches with it, doesn't crack, and doesn't peel.
• Transfer or flocking: the design is glued on top. It stays rigid, cracks when the fabric stretches, and eventually peels off in the wash.

For a BJJ rash guard, stretched every single session, printing into the fiber is the only serious choice. Every Rashu design is printed this way, across the whole garment.

4. Competition rules

In no-gi IBJJF and AJP

• Form-fitting top, long enough to cover the torso down to the shorts.
• Black, white, or black and white base.
• At least 10% of your belt color. The 50% figure often mentioned isn't actually in the rulebook.
• A top entirely in your rank color is also accepted.
• Short or long sleeve: both are allowed.

A rash guard that follows these rules is called a "ranked" rash guard. Full-surface illustrated designs aren't: they're made for training and open-rules tournaments.

Source: IBJJF uniform rules, reviewed on 2026-10-23.

In the gi

In IBJJF, a rash guard under the gi jacket is mandatory for women, with no color rule, and forbidden for men. For training, each club sets its own rule: many practitioners wear one under the gi for hygiene and comfort.

In ADCC and open-rules events

No color is imposed. Only pockets, zippers, and hard pieces are forbidden. Every design is allowed.

5. Size

• Long sleeve: this model runs big. Take your usual size; between 2 sizes, or for a compression fit, size down.
• Short sleeve: compression cut, very close to the body. Take your usual size; between 2 sizes, size up for more room.
• For competition: the same size. The top doesn't move.

Our quick-pick guide

Every model built for the mat is in the BJJ rash guard collection.

Rash guard or compression shirt?

The 2 look alike on a hanger, not on the mat. The rash guard is the combat piece, illustrated across the whole surface. The compression shirt is a plain, understated base, for the gym, strength training, or under another outfit.

The full detail is in our guides what is a rash guard and can you run in a rash guard. See also the compression shirts.

Care in 5 steps

A well-cared-for rash guard lasts years of training. Heat is its number 1 enemy: it wears out the elastane.

Out of the bag as soon as the session ends, inside out, at 30°C max, no fabric softener, air dry. The full detail is on the rash guard care page.

Our verdict

The best BJJ rash guard is the one you forget about during a roll. Start with 1 training top in a design you like. If you're aiming for IBJJF, add 1 ranked top in your belt color.

Test yourself

Frequently asked questions