A motorcycle helmet only does its job when it fits right. A loose helmet can rotate during impact. A tight one gives you a headache after thirty minutes. Both fail the rider in different ways.
The good news: getting your size right takes one minute, one tape measure, and one number.
What you need
- A flexible cloth or vinyl tape measure (the kind a tailor uses). A rigid metal tape won’t work — it can’t curve around your head smoothly.
- A mirror, a friend, or a phone camera so you can see what you’re doing.
- Sixty seconds.
No tape measure? Use a piece of string, then lay the string flat against a ruler.
Step 1 — Find the crown band
Wrap the tape around your head about 1 inch (2.5 cm) above your eyebrows, around the fullest part of the back of your skull. The line should run roughly parallel to the floor, level from one ear to the other.
Don’t measure higher than that — the widest part of most heads sits right above the brow, not at the crown.
Step 2 — Snug, not tight
Pull the tape comfortably snug. A finger should barely slide between the tape and your skin. If two fingers fit, you’re already measuring loose — and you’ll end up a size too big.
Read the number where the tape meets itself. Centimeters are easier for helmets — every reputable manufacturer publishes sizing in centimeters first.
Step 3 — Measure twice
Take a second reading from a slightly different starting point. If the two numbers are within 0.5 cm of each other, average them. If they’re more than 1 cm apart, measure a third time — your tape probably slipped.
Use the larger reading as your true head circumference.
| Size | Head (cm) | Head (in) |
|---|---|---|
| S | 55 – 56 cm | 21.7" – 22.0" |
| M | 57 – 58 cm | 22.4" – 22.8" |
| L | 59 – 60 cm | 23.2" – 23.6" |
| XL | 61 – 62 cm | 24.0" – 24.4" |
Not every model carries every size. Frankie Shiny Purple, Extreme Matte Pink, and Shanghai Matte Pink ship in S/M/L. Most other helmets in our lineup ship in M/L/XL.
Between sizes? Size down.
This is the rule most riders get wrong. If your measurement falls between two sizes — say, 58.5 cm — order the smaller one.
Helmet liners and EPS foam compress 3–5% in the first 15–20 hours of wear. A snug helmet on day one breaks in to a perfect fit by week two. A loose helmet on day one gets looser, and a loose helmet rotates during impact.
Sizing down between sizes is the standard recommendation across the helmet industry — and we follow the same rule.
How to tell it fits right
Put the helmet on. Fasten the chin strap. Then check four things:
- The cheek pads touch your face without painfully pinching. Light pressure is correct — the pads will compress.
- You can’t slide a finger between the brow pad and your forehead. If you can, the helmet is too loose.
- Grab the chin and try to roll the helmet up off your head. It shouldn’t move. If it lifts, too loose.
- Wear it for 20 minutes. No throbbing. No hot spots. Light pressure that fades is normal — sharp pressure isn’t.
If it doesn’t fit when it arrives
EDGE® offers a 30-day return window on unused helmets in original packaging. Your first size exchange ships free. Email us at support@edgehelmetsus.com with your order number and we’ll set you up.
Now that you have your number, see what fits. Every EDGE® helmet is DOT certified — Boston, Extreme, and Shanghai also carry ECE R22-06.
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