Driving yourself crazy trying to crochet the correct size hat? Here is your answer – a complete list of head and hat measurements as you crochet and knit hats so you can get the perfect size.
Basically, you take the head measurement and subtract it by one to one and a half inches to get the measurement for the finished hat, since the hat will stretch. Of course, that really depends on the stretch of your yarn, hook or needle size, and your gauge! I know, sorry it can’t be simpler. For instance, Sugar’n Cream yarn is 100% cotton and has very little stretch, but acrylic yarn (like Lion Brand’s Vanna’s Choice yarn) has a lot of stretch. So, plan accordingly! For me, that means I end up experimenting a lot and unraveling some work. However, I must say that I’ve made many a hat that wasn’t just the right size, most of them a little too big, and, with the exception of preemies and newborns, the hats looked great on each lucky head.
Now, if you have a math brain, Inner Child Crochet says you can take the head measurement, subtract 15%, and then divide by pi (3.14). Bet you thought you’d never have to use that again, did ya? Especially not for crafts! I did test this out on one of my hats – I folded the hat in half and measured the distance across (not perfectly accurate, but close enough for me). The distance is 9 inches, so multiply that by 2 to get the circumference – 18 inches. Take 15% of 18 (or multiply by .85), and you get 15.3, then divide by 3.14 and you get 4.87, which is about the diameter of the crown of my hat!
For the hat circumference, measure from the forehead all the way around. For the hat height, measure from the crown of the head to the base of the ear for winter hats, but for summer hats that have a brim and rest above the ears, only measure to the top of the ear. Take a look at Wooly Wormhead’s pictures for more help.
Head Circumference: 13 to 14 inches (33 to 36 cm)
Hat Circumference: 11.5 to 13 inches (29 to 33 cm)
Hat height (winter hat): 5.5 to 6 inches (13 to 15 cm)
Baby – 3 to 6 months
Head Circumference: 14 to 17 inches (36 to 43 cm)
Hat Circumference: 12.5 to 14 inches (32 to 36 cm)
Hat height (winter hat): 6.5 to 7 inches (15 to 18 cm)
Baby – 6 to 12 months
Head Circumference: 16 to 19 inches (41-48 cm)
Hat Circumference: 14.5 to 16 inches (37 to 41 cm)
Hat height (winter hat): 7.5 to 8 inches (19 to 46 cm)
Toddler – 12 months to 3 years
Head Circumference: 18 to 20 inches (46 to 48 cm)
Hat Circumference: 16.5 to 18 inches (42 to 46 cm)
Hat height (winter hat): 8 inches (20 cm)
Child – 3 to 10 years
Pre-Teens and Teens
Head Circumference: 20.5 to 22 inches (53 to 56 cm)
Hat Circumference: 19 to 20.5 inches (48 to 52 cm)
Hat Height (winter hat): 9 to 10 inches (25 cm)
Head Circumference: 21.5 to 22.5 inches
Hat Circumference: 20 to 21.5 inches (48 to 57 cm)
Hat height (winter hat): 11 inches (28 cm)