If shoes of the right length still pinch, or slip, the problem may be width. Shoe width is marked with letters such as B, D and E, and the letters have different meanings for women and men. This calculator takes your US size and the width across the ball of your foot and tells you which letter fits.
How to use the shoe width calculator
- Measure your width. Stand on paper with your usual socks, trace the foot, and measure across the widest part of the ball of the foot.
- Choose women’s or men’s and enter your US size.
- Enter the width in inches or centimetres.
- Read the letter. Wider than the chart means you should look at EE or 4E ranges.
Shoe width formula (chart lookup)
standard width: women B, men D
N / M / W: M = B (women) or D (men)
The widths come from the size.ly shoe width charts for US sizes 5 to 12, and the letter scale from Wikipedia’s Shoe size article, which states that the unlettered D is the norm for men and B for women (retrieved 2026-10-15). A measurement on a chart value belongs to that letter; one in between goes to the next wider letter.
Women
| US women | A narrow (in) | B medium (in) | C/D wide (in) | E extra wide (in) |
|---|---|---|---|---|
| 5 | 2.8 | 3.2 | 3.55 | 3.95 |
| 6 | 2.95 | 3.3 | 3.7 | 4.05 |
| 7 | 3.05 | 3.45 | 3.8 | 4.2 |
| 8 | 3.2 | 3.55 | 3.95 | 4.3 |
| 9 | 3.3 | 3.7 | 4.05 | 4.45 |
| 10 | 3.45 | 3.8 | 4.2 | 4.55 |
| 11 | 3.55 | 3.95 | 4.3 | 4.7 |
| 12 | 3.7 | 4.05 | 4.45 | 4.8 |
Men
| US men | C narrow (in) | D medium (in) | E wide (in) |
|---|---|---|---|
| 5 | 3.2 | 3.4 | 3.6 |
| 6 | 3.3 | 3.5 | 3.7 |
| 7 | 3.4 | 3.6 | 3.8 |
| 8 | 3.5 | 3.8 | 3.9 |
| 9 | 3.6 | 3.9 | 4.1 |
| 10 | 3.8 | 4.0 | 4.2 |
| 11 | 3.9 | 4.1 | 4.3 |
| 12 | 4.0 | 4.3 | 4.4 |
Worked example
A woman in a US 8 with a 3.6 inch ball width.
- US 8: B (medium) is 3.55 in and C/D (wide) is 3.95 in.
- 3.6 is just above B, so the next letter is C/D (wide) (3.95 in (10.0 cm)).
- A foot only 0.05 in over the B width may still be comfortable in a B with a roomy toe box.
Choosing the right width
- Toe box: look for a shape that matches your foot as well as the letter.
- Both feet: use the wider foot.
- Time of day: measure in the afternoon.
- Brand letters: some use N/M/W instead; see the notes above.
Pair this with the Shoe Size Calculator (foot length) for length. The result is general guidance based on one published chart.
Sources
Every figure above comes from these pages, read directly on the dates shown. Brand names are used only to identify published charts.
- Sizely — shoe width chart for men and women (ball-of-foot widths by US size) — checked 2026-10-15
- Wikipedia — Shoe size (width letters and defaults) — checked 2026-10-15
Frequently asked questions
What do the width letters mean?
In the North American system B is medium for women, D is medium for men, E is wide for men and extra wide for women, and EE is extra wide for men. Wikipedia describes the scale as AAA, AA, A, B, C, D, E, EE, EEE from narrowest to widest.
Why does the same letter mean different widths?
The width letter is relative to the length. A 3.8 inch foot is a B in a women’s size 10 but a C/D in a size 7, as the chart shows. The calculator uses your size row.
How do I measure my foot width?
Stand on a sheet of paper wearing the socks you will wear, trace the foot, and measure straight across the widest part, across the ball of the foot. Do both feet and use the wider one.
What do N, M and W mean?
Some brands use N for narrow, M for medium and W for wide. M is the same as B for women and D for men; W corresponds to D for women and E for men, so a women’s 9W is roughly a 9D.
Are widths the same in every brand?
No. Brands differ, and this page uses a published chart. For the length use the Shoe Size Calculator (foot length); for other countries the Shoe Size Converter (US/UK/EU/JP).