Baby hat sizing goes wrong for one reason: age labels. Two babies born the same week can sit a full size apart, because head circumference doesn't track neatly to months. The Nap Hat is sized by the centimetre for exactly this reason — so the only number that matters is the one around your baby's head.
Here's how to get it, read it, and check it.
The two-minute measure
Wrap a soft tape measure around the widest part of your baby's head, sitting just above the eyebrows and above the ears — the same line the hat's band will sit on. Keep it level, snug but not tight, and take the number in centimetres.
No soft tape? Wrap a length of string or ribbon around the same line, mark where it meets, then lay it flat against a ruler. It's as accurate as a tape for this.
Do it while they're calm — after a feed, on your lap. A wriggling measure reads long.
Match it to the chart
Your number maps straight to a size on our chart, from 34.6 cm at the smallest to 48.3 cm at the largest, across four sizes. See the exact ranges, in centimetres and inches, on the size guide — with a photo of the measure line so there's no ambiguity about where the tape sits.
Between two sizes? Size up.
If your measurement lands on the line between two sizes, take the larger one. The band is 95% cotton with 5% elastane, so it stretches onto a slightly bigger head and recovers to hold firm — the band still sits above the eyebrows, and the shade still rests over the eyes only. A size up buys you room to grow; a size down starts riding up within weeks.
How long each size actually lasts
A baby's head grows fastest in the first year — roughly 1 to 2 cm a month early on — which is why our 0–3, 3–6 and 6–12 month sizes each cover a genuinely different head. In practice, most babies spend two to four months in a size before the band starts sitting lower than it should. That's the signal to re-measure, not a fixed date: when the band slips toward the brows instead of resting above them, it's time for the next size. Buying the size up when you're close saves a second order later.
The 20-second fit check
Once it's on, four things tell you the size is right:
- The band sits snug just above the eyebrows — held in place, not gripping.
- No red marks when it comes off. A line pressed into the skin means size up.
- The shade rests over the eyes only — well clear of the nose and mouth.
- It stays put through a head-turn. If it rides up or slips down, the size is off, not the hat.
Get those four and you've got the fit the Nap Hat is designed around — the band above the eyes, the shade doing its one job, and nothing your baby wants to pull at.
Still unsure once it arrives? We accept 30-day returns on unworn items, so you can re-size for the right fit. For supervised daytime naps only.
