Baby Clothes Size and Age Chart

Mother holding baby boy (9-12 months), shopping for clothes
Ann Intrieri Paz/The Image Bank/Getty Images
By Stacie McClintock
Updated on 07/14/17

Buying baby clothes is a lot like playing the lottery; you hedge your bets on a number, and hope it's the right one.

But it doesn't have to be that way. While it's true that babies grow really fast, it is possible to buy clothes for them that will fit - at least for now. Use our size and age chart to help determine what size you should buy.

Remember: when in doubt, make your purchase based on weight and height rather than age! It's always safe to go one size bigger, except in the case of baby sleepwear.

US Size and Age Chart

Age/Size Weight Length Bootie/Shoe Size Sock Size
Newborn Up to 7 lbs Up to 17" N/A N/A
Up to 3 Months 7-12 lbs 17-23" 3 Up to 6 Months
3-6 Months 12-17 lbs 23-27" 4 Up to 6 Months
6-12 Months 17-22 lbs 27-29" 5 6-12 Months
12-18 Months 22-27 lbs 29-31" 6 12-24 Months
18-24 Months 27-30 lbs 31-33" 7 12-24 Months