Crochet hat sizes by age
A crochet hat should be smaller than the head it goes on. Yarn stretches, and a hat with no negative ease slides down over the eyes. The chart uses 10% negative ease, which suits most worsted and DK stitches. Increase it to 15% for very stretchy ribbing and reduce it to 5% for stiff stitches or bulky yarn.
| Age | Head (cm / in) | Hat (cm / in) | Height | Crown |
|---|---|---|---|---|
| Preemie | 25–32 / 9.8–12.6 | 25.7 / 10.1 | 11.4 cm / 4.5 in | 8.2 cm / 3.21 in |
| Newborn | 32–36 / 12.6–14.2 | 30.6 / 12 | 14 cm / 5.5 in | 9.7 cm / 3.83 in |
| 0 to 3 months | 35–40.5 / 13.8–15.9 | 34 / 13.4 | 15.2 cm / 6 in | 10.8 cm / 4.26 in |
| 3 to 6 months | 39.5–43.5 / 15.6–17.1 | 37.4 / 14.7 | 16.5 cm / 6.5 in | 11.9 cm / 4.68 in |
| 6 to 12 months | 42–47 / 16.5–18.5 | 40.1 / 15.8 | 17.8 cm / 7 in | 12.7 cm / 5.02 in |
| Toddler (1 to 2 years) | 45–49 / 17.7–19.3 | 42.3 / 16.7 | 19.1 cm / 7.5 in | 13.5 cm / 5.3 in |
| 2 to 4 years | 47.5–51 / 18.7–20.1 | 44.3 / 17.5 | 20.3 cm / 8 in | 14.1 cm / 5.55 in |
| 5 to 8 years | 50.5–53 / 19.9–20.9 | 46.6 / 18.3 | 21 cm / 8.25 in | 14.8 cm / 5.84 in |
| 9 to 12 years | 52–55.5 / 20.5–21.9 | 48.4 / 19 | 21.6 cm / 8.5 in | 15.4 cm / 6.06 in |
| Teen | 54–58 / 21.3–22.8 | 50.4 / 19.8 | 22.9 cm / 9 in | 16 cm / 6.32 in |
| Adult woman | 53–59.5 / 20.9–23.4 | 50.6 / 19.9 | 22.9 cm / 9 in | 16.1 cm / 6.34 in |
| Adult man | 55–60.5 / 21.7–23.8 | 52 / 20.5 | 24.8 cm / 9.75 in | 16.5 cm / 6.51 in |
How to use the crown diameter
Most top-down crochet hats start with a flat circle. Increase every round until the circle reaches the crown diameter in the chart, then stop increasing and work even until the hat reaches the height in the chart. The crown diameter is the finished hat circumference divided by pi (3.14).
For a slouchy hat, add 2 to 3 inches (5 to 8 cm) to the height. For a beanie that just covers the ears, use the height as given. For a folded brim, add the brim depth twice.
Newborn and baby crochet hat sizes
Newborn heads average about 34 cm (13 ⅜ in), so a newborn hat should be about 30 to 32 cm (11 ¾ to 12 ½ in) around and 14 cm (5 ½ in) tall. Preemie sizes vary a lot; if you are making hats for a hospital, ask the unit for their preferred dimensions.
Fit tips
- Always check gauge. A hat that is 2 stitches off per 4 inches ends up a full size wrong.
- Measure the person if you can. Age charts are averages and real heads vary by 3 to 4 cm within an age group.
- Block the hat over a bowl or balloon of the target circumference to set the size.