Baby and toddler shoe sizes are set by foot LENGTH, not age, so measure the foot first. In the US, a roughly 4.5-inch (11.3 cm) foot is about a size 4.5C, a 5-inch (12.6 cm) foot about 6C, and a 5.5-inch (14 cm) foot about 7.5C. Use the chart below, and re-measure every couple of months.
- Measure the bare foot heel-to-toe; the length in centimeters is the reliable number, not the age or the printed US size.
- US infant/toddler sizes run 0C to 13C (C = child), then restart at 1Y (Y = youth); one full size is only one third of an inch.
- A US size does not equal an EU or UK size: brands vary, and Nike in particular runs about one size large at the baby end.
- Under age two, feet often grow a half size every two to three months, so re-check the fit regularly.
What size shoe does my baby wear?
Your baby wears whatever size matches their foot LENGTH today, which is why two one-year-olds can be two full sizes apart. The single most accurate thing you can do is measure the bare foot, heel to longest toe, and read it against a chart rather than guessing from the birthday. If you are also sorting out clothes at the same time, our baby range (up to 24 months) and the baby clothes sizes by age guide pair naturally with this one.
We built the chart below by reconciling the published foot-length charts of six independent sources — See Kai Run, Carter's/OshKosh, Clarks, pediped, Nike, and the US barleycorn shoe-size standard — and stepping the ladder by the exact one-sixth-inch-per-half-size math, then checking every row against each chart. Values are the recommended maximum foot length for each size (measured with a little growing room).
Baby and toddler shoe size chart (US, EU, UK by foot length)
Measure the foot, find the centimeter range, then read across to the US, EU and UK size. The centimeter and inch columns are the anchor; treat EU and UK as close approximations.
| US size | Foot length (in) | Foot length (cm) | EU | UK | Approx. age |
|---|---|---|---|---|---|
| 0C | 2.95–3.12 | 7.5–7.9 | 16 | - | 0-6 weeks |
| 0.5C | 3.12–3.28 | 7.9–8.3 | 16 | 0 | newborn |
| 1C | 3.28–3.45 | 8.3–8.8 | 16 | 0.5 | 0-3 months |
| 1.5C | 3.45–3.62 | 8.8–9.2 | 17 | 1 | 2-4 months |
| 2C | 3.62–3.78 | 9.2–9.6 | 17 | 1.5 | 3-6 months |
| 2.5C | 3.78–3.95 | 9.6–10.0 | 18 | 2 | 5-8 months |
| 3C | 3.95–4.12 | 10.0–10.5 | 18.5 | 2.5 | 6-9 months |
| 3.5C | 4.12–4.28 | 10.5–10.9 | 19 | 3 | 8-11 months |
| 4C | 4.28–4.45 | 10.9–11.3 | 19.5 | 3.5 | 9-12 months |
| 4.5C | 4.45–4.62 | 11.3–11.7 | 20 | 4 | 11-14 months |
| 5C | 4.62–4.78 | 11.7–12.1 | 21 | 4.5 | 12-16 months |
| 5.5C | 4.78–4.95 | 12.1–12.6 | 21.5 | 5 | 14-18 months |
| 6C | 4.95–5.12 | 12.6–13.0 | 22 | 5.5 | 16-20 months |
| 6.5C | 5.12–5.28 | 13.0–13.4 | 22.5 | 6 | 18-24 months |
| 7C | 5.28–5.45 | 13.4–13.8 | 23.5 | 6.5 | ~2 years |
| 7.5C | 5.45–5.62 | 13.8–14.3 | 24 | 7 | 2-2.5 years |
| 8C | 5.62–5.78 | 14.3–14.7 | 24.5 | 7.5 | 2-2.5 years |
| 8.5C | 5.78–5.95 | 14.7–15.1 | 25.5 | 8 | 2.5-3 years |
| 9C | 5.95–6.12 | 15.1–15.5 | 26 | 8.5 | 2.5-3 years |
| 9.5C | 6.12–6.28 | 15.5–16.0 | 26.5 | 9 | ~3 years |
| 10C | 6.28–6.45 | 16.0–16.4 | 27 | 9.5 | 3-3.5 years |
| 10.5C | 6.45–6.62 | 16.4–16.8 | 27.5 | 10 | ~3.5 years |
| 11C | 6.62–6.78 | 16.8–17.2 | 28 | 10.5 | 3.5-4 years |
| 11.5C | 6.78–6.95 | 17.2–17.6 | 28.5 | 11 | ~4 years |
| 12C | 6.95–7.12 | 17.7–18.1 | 29.5 | 11.5 | 4-4.5 years |
| 12.5C | 7.12–7.28 | 18.1–18.5 | 30 | 12 | ~4.5 years |
| 13C | 7.28–7.45 | 18.5–18.9 | 31 | 12.5 | 4.5-5 years |
| 13.5C | 7.45–7.62 | 18.9–19.3 | 31.5 | 13 | ~5 years |
Recommended max foot length per size, reconciled from six published charts; the ladder continues into youth sizes (1Y and up) after 13C. Always confirm against the specific brand's own chart.
- We reconciled the published foot-length charts of six independent sources: See Kai Run, Carter's/OshKosh, Clarks, pediped, Nike, and the US barleycorn shoe-size standard.
- We anchored the ladder at US 4C = 11.30 cm (the tight median of the specialist charts) and stepped every half size by exactly one sixth of an inch (4.23 mm), the real US kids sizing increment.
- Every row was then checked against each published chart. Where a brand disagreed (Nike runs about a size large at the baby end), we treated it as an outlier instead of averaging it in.
- Agreement is strongest from 3C through 13C, where three or more sources line up; the very smallest sizes rest on fewer charts.
How do US baby and toddler shoe sizes work, and what does 3C mean?
US kids' shoe sizes are a length-based ladder where each full size adds exactly one third of an inch (about 8.5 mm) and each half size adds one sixth of an inch. The letter tells you which part of the ladder you are on: C stands for child (also called little kid, the baby-and-toddler range from 0C to 13C), and Y stands for youth (big kid, starting again at 1Y). So “3C” simply means child size 3, which fits a foot of roughly 4 inches (10 to 10.5 cm), typically around six to nine months old.
One quirk trips everyone up: the numbers reset. The ladder climbs 0C, 1C, up to 13C, and then the very next size is 1Y, not 14C. A 13C and a 1Y are only one third of an inch apart, even though the labels look far apart. To translate a US size into the EU (Paris-point) or UK system, use our baby size converter rather than assuming the numbers line up, because they do not.
How do I measure my baby's foot at home?
Measuring takes two minutes with a piece of paper and a ruler, and it beats every age chart. Do this:
- Put a sheet of paper against a wall and stand your baby on it, heel to the wall, with their full weight on the foot (measure standing, not sitting — the foot spreads).
- Mark the tip of the longest toe (not always the big toe), then measure from the wall edge to the mark in centimeters.
- Measure both feet and use the LARGER one; do it late in the day, when feet are at their biggest.
- Match that length to the chart above, then add a little growing room as described below.
If a foot lands right on the line between two sizes, size up — a shoe that is a hair long is fine, while a short one cramps the toes.
How much growing room should a baby shoe have, and how often do sizes change?
Most fitters leave about half an inch (roughly 1.3 cm) of space beyond the longest toe, which is why the chart sits a touch below the pure foot-length math — that room is already built in. You want about a thumb's width at the toe with the shoe on and the child standing; more than that and the shoe slips at the heel, less and it is already too small.
Feet grow fast early: under age two it is common to move up a half size every two to three months, so re-measure that often and check that a current pair has not gone tight. On whether babies need shoes at all and how footwear relates to foot development, we point you to the authorities rather than give a verdict: the American Academy of Pediatrics (HealthyChildren.org) and the American Podiatric Medical Association note that pre-walkers mainly need shoes for warmth and protection and that soft, flexible footwear suits developing feet. This guide is about fit and sizing only.
This is a fit and sizing guide, not medical or podiatric advice. For foot-health and shoe-timing questions, follow the named authorities linked above. See our medical disclaimer.
Why does my baby wear a different shoe size in every brand (US vs EU vs UK)?
Because a shoe size is a label each brand prints its own way, so the same foot can be a 4.5C in one brand and a 5C in another. Two things cause most of the gap. First, brand cut: some run generous, some snug, and one clear outlier is Nike, which runs about a full size large at the baby end — it labels an 11 cm foot a 5C where See Kai Run, Carter's and Clarks call the same foot about 4 to 4.5C. Second, the conversion systems do not line up cleanly: EU uses Paris points and UK numbering resets after 13.5, so the EU and UK columns are typical, not exact.
The fix is the same one that works for clothes: trust the measurement, not the number on the box. Keep your child's foot length in centimeters handy, confirm it against each brand's own chart, and see our baby clothing sizes by brand guide for how far this label-to-label drift runs across the wardrobe. Sizing the clothes for the same age? Our what size does a 1-year-old wear guide covers the 12M to 24M range, and the toddler range (2T and up) is the next step after that.
- Measure both bare feet standing, late in the day, and use the larger length in centimeters.
- Read the cm to a US size on the chart; if between sizes, size up.
- Leave about a thumb's width (half an inch) of growing room; no more.
- Re-measure every two to three months under age two, and confirm each brand's own chart.
Shop our baby range by size and use our size tools so you never guess a fit again.
Shop baby by sizeFrequently asked questions
What size is 3c in baby shoes
Size 3C is US child size 3, which fits a foot of about 3.95 to 4.12 inches or 10 to 10.5 centimeters, roughly six to nine months old. Because sizes are length-based, measure the foot rather than relying on the age, and confirm the fit against the specific brand's chart.
How do I measure my baby foot for shoes
Stand your baby on a sheet of paper with their heel against a wall and full weight on the foot, mark the longest toe, and measure the length in centimeters. Measure both feet, use the larger one, do it late in the day, and match the length to a size chart.
What shoe size does a 1 year old wear
Many one-year-olds wear about a US 4.5C to 5C, which fits a foot of roughly 4.5 to 4.8 inches or 11.3 to 12.1 centimeters, but feet vary widely at this age. Measure the foot instead of guessing, since two one-year-olds can be two full sizes apart.
Is US baby shoe size the same as EU or UK
No. A US size does not equal an EU or UK size, and the systems do not line up cleanly because EU uses Paris points and UK numbering resets. The centimeter foot length is the reliable anchor; treat EU and UK equivalents as close approximations and confirm each brand's own chart.
How often do baby shoe sizes change
Under age two, feet often grow about a half size every two to three months, so re-measure that often and check that current shoes have not gone tight. Growth slows after age two but you should still confirm the fit each time you buy.
Sources: See Kai Run sizing chart; Carter's / OshKosh B'gosh footwear size chart; Clarks kids size chart (US/UK/EU/cm); pediped foot-size chart; Nike Kids' footwear size chart; US barleycorn shoe-size standard; foot-health guidance from the American Academy of Pediatrics and the American Podiatric Medical Association.
