Baby hat sizes by age
These head circumferences are typical ranges. A baby at the top of a range usually needs the next size up.
| Age | cm | Inches | US |
|---|---|---|---|
| Preemie | 25 – 32 | 9.8 – 12.6 | – |
| Newborn | 32 – 36 | 12.6 – 14.2 | – |
| 0 to 3 months | 35 – 40.5 | 13.8 – 15.9 | – |
| 3 to 6 months | 39.5 – 43.5 | 15.6 – 17.1 | – |
| 6 to 12 months | 42 – 47 | 16.5 – 18.5 | – |
| Toddler (1 to 2 years) | 45 – 49 | 17.7 – 19.3 | – |
How to measure a baby’s head
- Use a soft tape measure while your baby is calm or asleep.
- Wrap it around the widest part of the head: just above the eyebrows and ears and around the back.
- Keep it snug but not tight, and measure twice.
- Add about 1 cm (⅜ in) for a structured sun hat. Knit hats need no extra.
European baby hat sizes
In Europe and the UK, baby hats are often labelled by head circumference in centimetres, such as 35, 37, 39 or 41, or by age in months. A hat labelled 39 fits a head of about 39 cm. Use the EU result in the calculator for these.
Fit tips
- Newborn hats are outgrown within weeks. Buy 0 to 3 months if you want more wear.
- Sun hats for babies should have a chin strap and a brim of at least 5 cm.
- Take hats off for sleep indoors, because babies release heat through their head.