Sock Foot Circumference Chart
Typical foot circumference for socks, baby to adult, in centimetres and inches.
The one measurement a sock has to fit is the circumference around the ball of the foot — the widest part it stretches over. This chart collects the foot circumferences crafters commonly knit socks to, from a baby to an adult, in both centimetres and inches. There is no single official sock-size standard, and foot width varies a lot from person to person at the same shoe size, so treat these as representative starting points and measure the actual foot whenever you can.
Foot circumference by sock size
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| Sock size | Foot circumference (cm) | Foot circumference (in) |
|---|---|---|
| Baby (0–12 months) | 12 | 4.5 |
| Toddler (1–3 years) | 15 | 6 |
| Child (3–10 years) | 18 | 7 |
| Adult Small | 20 | 8 |
| Adult Medium | 22 | 8.5 |
| Adult Large | 24 | 9.5 |
| Adult X-Large | 26 | 10 |
Circumference is measured around the ball of the foot; inches are rounded to the nearest half inch. Once you have a circumference, the Sock Size Calculator turns it into a cast-on from your gauge and a little negative ease.
Good to know
- These are representative foot circumferences, not an official standard — foot width varies a lot at the same shoe size, so measure around the ball of the foot directly whenever you can.
- Circumference is measured around the ball of the foot, the widest part, not around the ankle or the leg. That is the measurement the sock has to stretch over to go on.
- Socks are knit with negative ease, a little smaller than the foot, so they grip and stay up. These are the foot measurements, not the finished sock — the calculator subtracts the ease for you.
FAQ
- What is an average adult foot circumference?
- Around 22 cm (about 8.5 in) is a common adult medium, with adult feet spanning roughly 20 to 26 cm around the ball. Feet vary a lot at the same shoe size, so measure rather than relying on the average.
- Is foot circumference the same as shoe size?
- No. This chart is foot circumference — the distance around the ball of the foot — not a shoe size or a foot length. Two people in the same shoe size can have quite different foot widths, which is why sock fit is set by circumference.
- Should I measure foot circumference or foot length for this chart?
- Circumference — the way around the ball of the foot — is what this chart lists and what decides the number of stitches around. Foot length sets how far to knit before the toe, but it is a separate measurement and is not on this chart.
- How do I turn a foot circumference into a stitch count?
- Work a gauge swatch, then the Sock Size Calculator combines your gauge, the circumference from this chart and a little negative ease to give the exact number of stitches to cast on.