How to Measure Your Feet Correctly

What you need

• A sheet of paper larger than your foot (A4 or letter).
• A hard floor and a wall.
• A pencil.
• A ruler or tape measure with millimeters.
• The sock thickness you plan to wear.

The method

1. Place the paper flat against a wall on a hard floor. Slippers off, socks on.
2. Stand on the paper with your heel touching the wall — put your weight on that foot.
3. Mark the tip of your longest toe. It is not always the big toe.
4. Step off and draw a straight line from the wall edge to the mark. Measure it in millimeters.
5. Repeat for the other foot.

Use the longer foot

Almost no one has perfectly symmetrical feet. A few millimeters of difference is normal, but you should always buy for the longer foot. A shoe that is half a size too small on the longer foot is the single most common source of foot pain — well ahead of any width, arch, or cushioning issue.

Measuring width

For width, wrap a tape measure around the widest part of the foot (the ball) and record the circumference in centimeters. Brands publish width categories — Narrow, Regular (medium), Wide, Extra Wide — that are keyed to that circumference. If your ball measurement is more than one width above the mid-range for your length, order the wider option; a shoe that fits in length but crushes the metatarsals is the same amount of pain as one that's too short.

Turning millimeters into a size

Once you have a length in millimeters, ignore your habitual size and look at the brand's own chart. A 268 mm foot is a US men's 9.5, an EU 43, a UK 9 — but a Nike 43 and a Salomon 43 are built on different lasts, so the width and volume will differ even at the same nominal length. The length is where you start; the fit notes are how you finish.

Kids' feet grow fast

Children's feet grow up to 1.5 mm per month during peak growth years. Measure every three months from age two to age ten. Buy with 12–15 mm of room in front of the longest toe, not 5 mm — 'a bit of growing room' is a real category, and shoes that fit perfectly on the day you buy them will be too small by month two.