Quick answer: To find your hat size, wrap a soft tape measure around your head about an inch above your ears and eyebrows — where a hat actually sits. Match that number to the chart below. If you land at 7½ or above, you have a big head, and standard hats will feel too tight or perch too high. That's exactly what MONGO is built for.
How to measure your head in 3 steps
- Wrap the tape where the hat rests — about one finger-width (roughly an inch) above your eyebrows and above your ears, around the widest part of the back of your head.
- Keep it level and snug — flat against your head, not tight, not loose.
- Read the measurement in inches and take it twice to be sure. That number is your head circumference — the only measurement that matters for hat sizing.
No tape measure? Use the string method
Wrap a piece of string or a phone charging cable around your head the same way, mark where it meets, then lay it flat against a ruler. That length is your head circumference. You can also download our printable size chart and measure at home.
Hat size chart
Match your head circumference to your size. Hat sizes come from a simple formula (circumference in inches ÷ 3.14), which is why the numbers look oddly specific.
| Head circumference | cm | US hat size | Standard hats? |
|---|---|---|---|
| 22" | 56 | 7 | Fits most |
| 22¾" | 58 | 7¼ | Fits most |
| 23⅛" | 59 | 7⅜ | Getting tight |
| 23½" | 60 | 7½ | Big-head territory — MONGO |
| 23⅞" | 61 | 7⅝ | Most hats too small |
| 24¼" | 62 | 7¾ | Most hats too small |
| 24⅝" | 63 | 7⅞ | Most hats too small |
| 25" | 64 | 8 | Most hats too small |
| 25⅜" | 65 | 8⅛ | Most hats too small |
| 25¾" | 66 | 8¼ | Most hats too small |
MONGO hats fit sizes 7½ to 8¼ — head circumferences from about 23½" to 25¾" (60–66 cm), and extend to roughly 68 cm fully snapped.
What counts as a "big head"?
Most "one size fits all" and standard fitted hats top out around 7⅜–7⅝. So once your head measures 7½ or larger (23½"+ / 60 cm+), you're in big-head range — and you've probably already felt it: hats that leave a red mark, sit too high like a cap balanced on top, or give you a headache by the end of the day.
That's not your head being "too big." It's the hats being built too small. Most hats scale width, not depth, so they run out of room in the crown. MONGO hats are built bigger all around — with a deeper crown — so the hat comes down where it should and actually fits.
What if I'm between sizes?
Because every MONGO hat is an adjustable snapback, you've got built-in flexibility — the snap closure covers a range rather than locking you into one exact size. If you measure right at the edge (say, 7⅜–7½), a MONGO will still fit comfortably where a standard cap would already be squeezing.
Found your size? Here's your hat
If you measured 7½ or above, you're exactly who we make these for. Shop XL hats for big heads →
Still deciding between styles? See our FAQ on hats for big heads.
Frequently asked questions
How do I measure my head for a hat?
Wrap a soft tape measure around your head about an inch above your eyebrows and ears — where a hat sits — keeping it level and snug. Read the number in inches and match it to a hat size chart. No tape measure? Use a string and a ruler.
What hat size is considered big?
Any size from 7½ and up (a head circumference of about 23½ inches / 60 cm or more) is considered a big head. Most standard hats stop fitting comfortably around this point.
What size hat is a 7¾?
A 7¾ hat fits a head circumference of about 24¼ inches (62 cm). It's a common big-head size that most standard hats don't offer — MONGO hats fit 7½ through 8¼.
Why don't regular hats fit my big head?
Most hats scale their width but not their crown depth, so they perch too high and squeeze rather than settle down over your head. MONGO hats are built with a deeper crown and more room all around.
What's the biggest hat size MONGO makes?
MONGO hats fit up to size 8¼ (about 25¾ inches / 66 cm), with adjustable snapback closures for a comfortable fit across the range.
