Baby Shoe Size Chart by Age: Newborn to 3 Years

Quick answer: most babies wear a US size 1 to 2 at birth, a size 3 to 4 by 9 months, a size 5 by their first birthday, a size 6 by 18 months, and a size 7 to 8 by age two. Each number is about a third of an inch longer than the last. The chart below gives the foot length for every size in inches and centimeters, with the EU and UK equivalents and the matching Grookz size. Ages are averages, so measure the foot when you can; the two-minute method is here, and the free size finder turns the measurement into a size.

Baby shoe size chart by age

EU and UK sizes are the closest standard equivalents; brands round differently, so treat them as a starting point. US infant sizes run 1 to 13 and then start over at youth size 1, which is why "size 4" can mean a 9-month-old or a 4-year-old depending on who's talking. Our post on what age each number size fits covers that scale in detail.

How to use the chart

Read the foot length column first and the age column second. At 12 months, a healthy foot can be anywhere from 4.3 to 5.2 inches, which is three different sizes. Age gets you to the right part of the chart; the measurement gets you to the right row.

Then add growing room. A new shoe should have about half an inch (a thumb's width) between the longest toe and the end of the shoe. Less than that and toes curl; more than that and a new walker trips. For sock shoes and other stretchy styles, a quarter inch is enough because the knit gives.

Grookz sizes explained

Our sock shoes are sized by age range rather than by number, because the knit stretches and one size covers what would be two or three number sizes in a hard-soled shoe. These are the foot lengths each size fits, and they're the same numbers the size finder uses:

When a foot lands within a quarter inch of the top of a range, go up. A roomy sock shoe stays on because the cuff holds the ankle, and the foot grows into it within weeks. Our walkers, clogs, and moccasins use the same age ranges, with some styles running to 3 to 4 years or beyond; each product page lists what's available.

How to measure a baby's foot

Stand your baby on a sheet of paper (feet spread under weight, so standing beats sitting), hold the pencil upright, and mark the back of the heel and the tip of the longest toe. Measure between the marks. Do both feet and use the longer one. Evening measurements run slightly bigger than morning ones, which is fine; that's the foot you're fitting. The full measuring guide has a version for babies who won't stand still and one for toddlers who won't cooperate.

Shoe size by age, in more detail

Newborn to 6 months

A newborn foot is around 3.3 inches, a US size 0 or 1, and babies this age don't need shoes. Socks or a soft sock shoe keep feet warm and stay on better than socks alone. By 6 months most feet are about 4.1 inches, a size 3. The newborn sizing post has the month-by-month numbers for this stretch.

6 to 12 months

Crawling starts, and so does the case for a non-slip sole on hardwood and tile. Feet go from about 4.1 inches to 4.75 inches, size 3 to size 5, often in a single growth spurt. See 7 months and 9 months for what each stage needs.

12 to 18 months

First steps. The average 1-year-old foot is 4.75 inches, a US size 5, and the 1-year-old post explains how to fit a first walking shoe. By 18 months, feet are around 5.1 inches, a size 6. The 18-month post picks up there.

2 to 3 years

Growth slows to about half a size every three to four months. A 2-year-old foot is typically 5.5 inches (size 7), a 3-year-old's about 6.1 inches (size 9). Toddlers at this age can put on their own sock shoes, which is the main reason parents keep buying them; the toddler sock shoes post covers where they still work and where a firmer shoe is better.

How fast do baby feet grow?

About half a size every two months in the first year, half a size every three months in the second year, and half a size every four months or so from age two to three. Check the fit every six to eight weeks in the first two years. The signs a shoe is too small: red marks on the toes or heel after wear, toes curled inside the shoe, a sock shoe that's suddenly hard to pull over the heel, or a baby who starts pulling at shoes they used to ignore. Our post on why babies hate shoes starts with the size for that reason.

Common sizing mistakes

• Buying by age alone. Age is an average. Foot length is the size.
• Sizing to the smaller foot. Most people have one foot slightly longer. Fit that one.
• Buying two sizes up to save money. Half an inch of room is right. A shoe that's too long flops at the heel and trips a new walker.
• Ignoring width. Baby feet are wide at the toes. A shoe that fits for length but squeezes the toes is the wrong shoe. Soft knit uppers and wide toe boxes solve this.
• Trusting last season's measurement. Feet grow in spurts. Re-measure before every purchase.

Frequently asked questions

What size shoe does a 1-year-old wear?

Most 1-year-olds wear a US size 4 or 5, for a foot around 4.5 to 4.75 inches. In Grookz sizing that's Size 2 (7 to 12 months), moving to Size 3 once the foot passes 5 inches.

What size shoe does a 6-month-old wear?

Usually a US size 2 or 3, for a foot around 3.75 to 4.1 inches. That's a Grookz Size 1. Most 6-month-olds don't need shoes yet; a sock shoe for warmth and grip while crawling is enough.

What's the difference between infant, toddler, and kids' shoe sizes?

US sizes 1 to 13 run as one scale from infant through toddler, sometimes with a C after the number (4C means child size 4, the same as a plain 4). After 13, sizing restarts at youth size 1, which fits a 7-inch foot and typically a 5- to 6-year-old.

How much room should baby shoes have?

About half an inch between the longest toe and the end of the shoe for hard-soled shoes, and a quarter inch for stretchy sock shoes. Press the toe of the shoe while your baby stands to check.

How often should I measure my baby's feet?

Every six to eight weeks until age two, then every three months. Always before buying a new pair.