In shoe sizing, the "D" stands for the width of the shoe, not the length. It's a standard part of notations like 10D, where the number is length and the letter indicates width.

Men's vs. Women's Meaning

For men, D means medium or standard width —the most common fit, typically measuring 3.35–4.45 inches across the ball of the foot, suiting average builds.

Women’s shoes flip this: D signals wide width , beyond the default B (medium for women); a man's D often equals a woman's E or wider.

This difference arises from US sizing charts, where scales start narrower for women (A–C narrow, B medium, D+ wide) versus men (B narrow, D medium, E+ wide).

Width Scale Overview

Shoe widths follow this typical progression (US standards vary slightly by brand):

Width| Men’s Fit| Women’s Fit| Approx. Inches (Size 9 Men / 8 Women)
---|---|---|---
A| Extra Narrow| Narrowest| ~3.5 / 3.2 5
B| Narrow| Medium| 3.7 / 3.5 59
D| Medium| Wide| 3.8–4.0 / 3.7 17
E| Wide| Extra Wide| 4.2 / 4.0 5
EE| Extra Wide| Very Wide| 4.5+ 1

Why It Matters for Fit

Poor width match causes blisters, numbness, or pain—D ensures toes aren't cramped (men) or overflowing (women with broader feet).

Pro Tip : Measure both feet at day's end (they swell); trace on paper, check ball-of-foot width. Brands like New Balance label clearly; try in-store as D varies (e.g., athletic vs. dress shoes).

As of 2026, online forums buzz with D confusion in kids' sizing too—often medium like men's, but always check charts.

Quick Fit Hacks

  • Narrow feet? Drop to B or A; add insoles for D shoes.
  • Wide feet? Go E/EE or stretchers; Vessi-like brands offer adjustable D fits.
  • Story Time : I once grabbed "10D" assuming universal medium—bliss for my average guy's foot, but my partner (wide-footed woman) needed 9D instead. Lesson: Gender scales save sanity!

TL;DR : D = medium width for men, wide for women—measure up for happy feet.

Information gathered from public forums or data available on the internet and portrayed here.