Kids shoe sizes are assigned by foot length, not age. Two children of the same age can differ by two full shoe sizes. Always measure your child's foot before buying — especially for online purchases — rather than relying on their current size or age alone.
How to measure a child's foot
- Have the child stand on a piece of paper (standing spreads the foot to its full length).
- Place their heel against a wall and mark the tip of the longest toe.
- Measure from the wall to the mark in inches or centimeters.
- Measure both feet and use the longer measurement.
- Add 0.5 inch (1.25 cm) for growing room.
US kids shoe size chart
| US Size | Foot length (in) | Foot length (cm) | Approx. age |
|---|---|---|---|
| 1C (infant) | 3.5 in | 8.9 cm | 0–3 months |
| 2C | 3.75 in | 9.5 cm | 3–6 months |
| 3C | 4.25 in | 10.8 cm | 6–9 months |
| 4C | 4.5 in | 11.4 cm | 9–12 months |
| 5C | 5.0 in | 12.7 cm | 12–18 months |
| 6C | 5.5 in | 14.0 cm | 18–24 months |
| 7C | 5.75 in | 14.6 cm | 2 years |
| 8C | 6.125 in | 15.6 cm | 2–3 years |
| 9C | 6.5 in | 16.5 cm | 3 years |
| 10C | 6.75 in | 17.1 cm | 3–4 years |
| 11C | 7.125 in | 18.1 cm | 4–5 years |
| 12C | 7.5 in | 19.1 cm | 5 years |
| 13C | 7.75 in | 19.7 cm | 5–6 years |
| 1Y (youth) | 8.125 in | 20.6 cm | 6–7 years |
| 2Y | 8.5 in | 21.6 cm | 7–8 years |
| 3Y | 8.875 in | 22.5 cm | 8–9 years |
| 4Y | 9.25 in | 23.5 cm | 9–10 years |
| 5Y | 9.625 in | 24.4 cm | 10–11 years |
| 6Y | 9.875 in | 25.1 cm | 11–12 years |
| 7Y | 10.25 in | 26.0 cm | 12–13 years |
US to EU and UK shoe size conversion
| US Kids | EU Size | UK Kids |
|---|---|---|
| 4C | 19–20 | 3.5 |
| 5C | 21 | 4.5 |
| 6C | 22 | 5.5 |
| 7C | 23 | 6 |
| 8C | 24–25 | 7 |
| 9C | 25–26 | 8 |
| 10C | 27 | 9 |
| 11C | 28–29 | 10 |
| 12C | 30 | 11 |
| 13C | 31 | 12 |
| 1Y | 32–33 | 13 |
| 2Y | 33–34 | 1 |
| 3Y | 35 | 2 |
| 4Y | 36 | 3 |
| 5Y | 37–38 | 4 |
| 6Y | 38–39 | 5 |
| 7Y | 40 | 6 |
When to re-measure
Children's feet grow quickly — check size every 2–3 months for children under 3, and every 3–6 months for older children. A shoe that fit 3 months ago may now be restricting. Signs a child has outgrown their shoes include toes touching the front, redness on the foot after removing shoes, or complaints of pinching.
Width matters too
US kids shoes often come in widths: M (medium/standard), W (wide), and occasionally N (narrow). A child with wide feet who wears standard-width shoes may experience discomfort even if the length is correct. When in doubt, choose a half-size larger and consider a wide-width option.
For a full age-by-age reference covering US, UK, EU, and Japan sizes from birth through age 10 with foot lengths, see the Kids Shoe Size Chart by Age →.