Kids’ shoe size
by age

Size by age

The typical foot is the middle one at that age: half of children are smaller, half bigger. The last column is the range nine children in ten fall within. Sizes are for that foot length, rounded up to the next size as our calculator does.

Under 2, feet were measured lying down; from 2, standing. “4 years” is the year from 3½ to 4½, and so on. UK children’s sizes run to 13.5, then adult sizes start again at 1. US kids’ sizes run 0C to 13.5C (C, sometimes written K), then 1Y to 7Y.

How feet grow

Feet grow fastest early: about 26 mm a year over the first two years (babies measured lying down), then about 10 mm a year from 2 to 4 and 9 mm a year from 4 to 10 (children standing). A US kids’ half size is 4.2 mm of foot, so on average a baby outgrows a half size in about 2 months, and a child of 2 to 10 in about 5.

Why age is only a guide

At 6, nine children in ten have feet between 16.2 cm and 19.8 cm: US 9.5C to 1.5Y, about 4½ sizes apart. Feet at either end of that range are common, and need a very different shoe from the “typical” size. At other ages the spread is 3 to 5 sizes.

Girls and boys

The survey also reports girls and boys separately (from age 2). Their typical feet are within 5 mm of each other up to 12; at 13, boys’ are 8 mm longer, and the gap grows from there.

Toddler, little kid, big kid

Shops and brands sort kids’ shoes into three bands. Where each band ends follows the brands’ own kids’ charts, which can differ by a size or so at the edges:

Measure instead

Measure with a photo: your child stands on a sheet of paper against a wall while you hold their heel, and you get their foot length and size. The photo stays on your phone. Or print the foot ruler, which has a kids’ version. The measuring guide has the steps for a tape measure.

Already have the length? Type it here:

About the numbers

The foot lengths come from a survey of American children made for the US Consumer Product Safety Commission (Snyder and colleagues, University of Michigan, 1977), which measured 2,950 children in the age groups shown. From age 2 each child stood with their weight evenly on both feet, and the right foot was measured from the heel to the longest toe. Babies under 2 were measured lying on their backs (225 babies, so those rows are less certain). The full tables are published by the US National Institute of Standards and Technology.

Feet differ between places and over time, and with how they’re measured. A 2022 survey of children in one district of Beijing, measured standing with a Brannock device, found these averages:

At the same ages, the US survey’s averages are 2 to 8 mm longer than these. Either way, a measured foot beats any average.

Questions