Crochet Hat Size Chart & Crown Calculator

Crochet hat sizes from preemie to adult: head size, hat height and how wide to make the crown, plus a calculator for any head with snug, regular or slouchy fit.

New to this? Read the guide, with an example

Who is it for?

Head circumference ()

Around the forehead, just above the ears and eyebrows.

Fit

make the hat

Around the hat
Crown circle across
Height, brim to top

Top-down hat: increase the crown in rounds until it’s across, then work even.

Write out the crown rounds Free crochet hat patterns

Crochet hat size chart

Typical head sizes by age, with a regular fit (the hat 1 in smaller than the head so it stays on). Measure if you can: heads vary a lot.

Crochet hat sizes by age: head circumference, hat circumference, crown diameter and height
Size	Head	Hat around	Crown across	Height
Preemie	12 in (30 cm)	11 in	3.5 in	4.5 in (11 cm)
Newborn	13.5 in (34 cm)	12.5 in	4 in	5.5 in (14 cm)
Baby 3–6 months	15 in (38 cm)	14 in	4.5 in	6 in (15 cm)
Baby 6–12 months	17 in (43 cm)	16 in	5.1 in	6.5 in (17 cm)
Toddler 1–3 years	18.5 in (47 cm)	17.5 in	5.6 in	7 in (18 cm)
Child 3–10 years	19.5 in (50 cm)	18.5 in	5.9 in	7.5 in (19 cm)
Teen	21 in (53 cm)	20 in	6.4 in	8 in (20 cm)
Adult small / woman	21.5 in (55 cm)	20.5 in	6.5 in	8.5 in (22 cm)
Adult medium / man	22.5 in (57 cm)	21.5 in	6.8 in	9 in (23 cm)
Adult large	23.5 in (60 cm)	22.5 in	7.2 in	9.5 in (24 cm)

Why a hat is smaller than the head

Crochet stretches, so a hat made to the exact head size slides down. Most hats are made 1–2 in (2.5–5 cm) smaller around than the head: that’s called negative ease. Beanies take the most; slouchy hats take almost none but are a couple of inches taller.

The crown: when to stop increasing

A top-down hat starts as a flat circle. Once the circle is as wide as the hat’s circumference divided by π (about 3.14), stop increasing and work even rounds for the sides. The flat circle calculator writes those crown rounds out for you.