Hat sizes by age
| Size | Head | Hat height | Finished hat (fitted) | Cast on, 20 sts / 4 in | Cast on, 24 sts / 4 in |
|---|---|---|---|---|---|
| Preemie (4–5 lb) | 12 in · 30 cm | 4.5 in · 11 cm | 10.8 in | 56 | 64 |
| Newborn | 14 in · 36 cm | 6 in · 15 cm | 12.6 in | 64 | 72 |
| Baby 3–6 months | 17 in · 43 cm | 7 in · 18 cm | 15.3 in | 80 | 88 |
| Baby 6–12 months | 18 in · 46 cm | 7.5 in · 19 cm | 16.2 in | 80 | 96 |
| Toddler 1–3 years | 19 in · 48 cm | 8 in · 20 cm | 17.1 in | 88 | 104 |
| Child 3–10 years | 20 in · 51 cm | 8.5 in · 22 cm | 18.0 in | 88 | 112 |
| Teen | 21 in · 53 cm | 10 in · 25 cm | 18.9 in | 96 | 112 |
| Adult woman | 22 in · 56 cm | 11 in · 28 cm | 19.8 in | 96 | 120 |
| Adult man | 23 in · 58 cm | 11.5 in · 29 cm | 20.7 in | 104 | 128 |
Head circumferences follow the Craft Yarn Council and Knit Picks charts; heights are the typical values from the Knit Picks chart and include room for a folded brim. "Finished hat" is the head size minus 10% negative ease for a ribbed knitted beanie. Cast-on numbers are rounded to a multiple of 8 and match the hat size calculator.
How to measure a head
- Wrap a soft tape measure around the head, just above the eyebrows and ears, where the brim will sit.
- Keep it snug but not tight, and read the measurement where the tape overlaps.
- For a baby or a gift, use the chart. Children grow fast, so for a gift you can go one size up.
Ease: why hats are smaller than heads
A hat that is exactly the size of the head slides off. Knitted ribbing stretches, so most beanies are knitted about 10% smaller than the head (1–2 in for an adult). Crochet stretches less, so crochet hats are usually made 0–5% smaller.
Hat height
- Fitted beanie without a fold: for an adult, around 8–9 in.
- Beanie with a folded brim: add the depth of the fold, about 2–3 in.
- Slouchy hat: 11–12 in or more, with little or no negative ease in the body.
Questions
What is the average adult head size?
Adult heads are usually 21–23 in (53–58.5 cm) for women and 22–24 in (56–61 cm) for men, according to the Craft Yarn Council chart.
What size hat for a newborn?
A newborn head is about 14 in (35.5 cm). A fitted newborn hat is about 12.5–13 in around and 5–6 in tall.
How much yarn for a hat?
An adult hat in worsted takes about 150 yards; a baby hat about 70 yards. Bulky yarn needs less length, fingering more.