Crochet size chart for babies: hats and booties by age

Head circumference and foot length for babies

Scroll the table sideways to see every column.

Age	Head on hat charts	Heads measured at that age	Foot length
newborn	13 to 14.5 in (33 to 37 cm)	12.4 to 15.3 in (31 to 39 cm), at birth	3.25 to 3.75 in (8 to 10 cm)
3 to 6 months	14 to 17 in (36 to 43 cm)	14.6 to 18.1 in (37 to 46 cm), from 3 to 6 months	4 to 4.5 in (10 to 11 cm)
6 to 12 months	16 to 19 in (41 to 48 cm)	15.7 to 19.2 in (40 to 49 cm), from 6 to 12 months	4.25 to 4.75 in (11 to 12 cm)
1 to 2 years	17 to 20 in (43 to 51 cm)	16.7 to 20.2 in (42 to 51 cm), from 1 to 2 years	4.5 to 5.5 in (11 to 14 cm)

Babies of one age differ a great deal, so every figure here is a range. Measure the baby if you can.
The charts we read differ, so each range runs from the smallest to the largest figure they give. Centimeters are worked out from the inches.
The third column is not from hat charts. It is heads as measured for two sets of growth charts, boys and girls together, leaving out the smallest 3 in 100 and the largest 3 in 100.
This chart has no chest size for sweaters: we found one chart of a baby's chest by age, and we print nothing that stands on one chart.

A chart is for when you cannot measure. Babies vary greatly, and a hat or a bootie made to a measured head or foot fits better than one made to an age.
Things made from yarn stretch, so a sock or bootie stretches to fit the foot.

How long is a newborn's foot for booties?: About 3.25 to 3.75 inches (8 to 10 cm).
What size are booties for 6 to 12 months?: The foot is about 4.25 to 4.75 inches (11 to 12 cm) long.
How big is a baby's head at 3 to 6 months?: Hat charts give 14 to 17 inches (36 to 43 cm). Heads measured at that age run from 14.6 to 18.1 inches (37 to 46 cm).

What chest size do I use for a baby sweater?: This chart has none: we found one chart of a baby's chest by age, and print nothing that stands on one chart. A sweater pattern states the chest measurement of each size. Measure around the baby's chest, or measure a sweater that fits, and choose the size from that.
Is a 0 to 3 months size the same as newborn?: For feet on this chart, yes: one of the charts we read calls its first size newborn and the other 0 to 3 months, and the newborn row holds both.
Where do I find sizes for older children and adults?: The hat size chart has head sizes from a preemie to an adult. Our suggestion

Abbreviations What does this abbreviation in my pattern mean?
US and UK terms What does this stitch name mean in US terms and in UK terms?
Chart symbols What does this symbol on a crochet chart mean?
Japanese chart symbols What does this symbol on a Japanese chart mean?
Terms in other languages What is this stitch called in a pattern written in another language?
Hook size for your yarn weight Which hook do I use with this yarn?
Hook size by project What size hook do I use for the thing I am making?
Hook size chart What size is my hook, in millimeters and as a US letter or number?
Steel hook sizes What size is my steel crochet hook in millimeters?
Knitting needle to hook size Which crochet hook is the same size as my knitting needle?
Yarn weight chart What weight is my yarn, and what else is it called?
Thread size chart How thick is this size of crochet thread?
Starting chain calculator How many chains do I start with for this width?
Yarn calculator How much yarn do I need to finish this?
Blanket size chart How big should I make this blanket?
Baby blanket size chart How big should I make a baby blanket?
Scarf size chart How long and how wide do I make a scarf?
Hat size chart How big is the head I am making this hat for?
Headband size chart How long do I make a headband or an ear warmer?
Slipper size chart How long is the foot for this shoe size?
All crochet tools