MMA Headgear Sizing Guide
Fit first. Protection second. Everything else follows.
ONX headgear comes in two sizes: Small/Medium and Large/X-Large, sized by head circumference and cross-referenced against hat size. Measure carefully. Get it right. The headgear that shifts mid-round isn't protecting you.
How to Measure
Head circumference is the only measurement you need. Here's how to take it correctly:
-
Grab a soft tape measure.
A fabric or flexible measuring tape gives the most accurate result. A rigid ruler won't contour to your head; avoid it. -
Position the tape just above your ears.
Wrap it around the widest part of your head: just above the ears and across the mid-forehead. This is the same reference point used for hat sizing. -
Keep it level and snug, not tight.
The tape should sit flat all the way around without compressing. Tilted or loose measurements will throw off your size. -
Record in both centimeters and inches.
Note both. Cross-reference against the chart below in whichever unit feels most natural.
Tip: Have someone else measure for you. Holding the tape yourself can cause it to tilt or shift slightly. Two seconds of help = a much more accurate result.
Headgear Sizing Chart
ONX headgear sizing is built on hat size. Use the chart below, along with the reference image, to find your fit.
| Size | Head Circ. (cm) | Head Circ. (inches) | Hat Size (fitted) |
|---|---|---|---|
| S / M | 54 cm | 21¼" | 6¾ |
| 55 cm | 21⅝" | 6⅞ | |
| 56 cm | 22" | 7 | |
| 57 cm | 22⅜" | 7⅛ | |
| L / XL | 58 cm | 22¾" | 7¼ |
| 59 cm | 23⅛" | 7⅜ | |
| 60 cm | 23½" | 7½ | |
| 61 cm | 23⅞" | 7⅝ | |
| 62 cm | 24¼" | 7¾ |
On the cusp between sizes? There's intentional overlap at 57–58 cm (22⅜"–22¾"). Fighters in this range can go with either S/M or L/XL and expect a solid, secure fit. When in doubt: if you prefer a locked-down feel, go S/M. If you have a thicker head shape, longer hair, or plan to wear wraps underneath, go L/XL.
How to Choose Your Size
Head circumference is your guide. Hat size is your cross-check. When one measurement puts you between options, use the guidance below.
Between sizes? Go smaller.
Headgear that fits is headgear that stays put. S/M runs to 57 cm (22⅜") and L/XL starts at 58 cm (22¾"). If your measurement falls in that range, the smaller size will lock in tighter. The adjustable rear lacing on both ONX headgear models compensates for minor variation.
At the top end of a size? Go larger.
If you're measuring at 57 cm and your head runs wide or round, L/XL may deliver better lateral coverage and less pressure during long sparring sessions.
Thicker hair or wraps?
Account for volume. Athletes with high-density or longer hair, or who wrap their heads before putting on headgear, should size up from their base measurement.
What a Proper Fit Looks Like
ONX headgear is engineered to stay in place. This is what you should expect when the fit is right, and what to watch for when it's off.
✓ Correct Fit
- Sits level across your brow; no forward tilt
- No shifting during movement or head rotation
- Clear, unobstructed peripheral vision
- No pressure points on temples or crown
- Chin strap snug but not pulling
- No need to readjust between rounds
✗ Too Tight
Headache or pressure after a few rounds. Leaves marks on your forehead. Vision feels restricted. Loosen lacing or size up.
✗ Too Loose
Shifts or rotates during movement. Drops over your eyebrows mid-round. Constantly needs adjusting. Size down or tighten rear lacing before going smaller.
Trevor Wittman: "If your headgear moves, you're not protected. This is built to stay in place so you can stay focused."
MMA Headgear Fit and Sizing How-To Video
Trevor Wittman explains how to fit and properly size your Elite Ultralight Headgear.
Why Proper Sizing Matters
Headgear that doesn't fit correctly isn't just uncomfortable; it's unsafe. Loose headgear rotates on impact, leaving your orbital and temple exposed. Tight headgear restricts blood flow and kills your focus by the second round.
The ONX Elite Ultralight and Precision Line headgear are both engineered with full-face coverage: padded brow, orbitals, temples, and chin. That coverage only functions correctly when the gear is properly seated on your head. Microcellular polyurethane foam can only absorb and disperse impact when the padding makes consistent contact with the right zones.
Fit is not optional. Measure first. Size right. Train without compromise.
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