When you’re shopping for new shoes, have you ever noticed that some styles have letters next to the size, such as ‘B’ and ‘M’? What do these letters mean, and do they affect the comfort of the shoes? In the following, I’ll explain their meanings to help you avoid sizing pitfalls and ensure every step you take is comfortable.
Basic Knowledge of Shoe Sizes: B and M
Actually, M and B are also part of shoe sizing, but they represent the width, not the length. Let’s dive into these two letters to get a full understanding of the shoe width sizing system.
Shoe Width Sizing Chart
| Width Indicator | Women’s Shoe | Men’s Shoe |
| 4A（AAAA） | Extra Narrow | – |
| 3A（AAA） | Very Narrow | – |
| 2A（AA） | Narrow | – |
| A | Slightly narrower than standard | – |
| B | Standard Width (Women’s Medium) | Extra Narrow |
| C | Slightly Wider than Standard | Narrow |
| D | Very Wide | Standard Width (Men’s Medium) |
| E | Extra Wide | Slightly Wider than Standard |
| 2E（EE） | Extra Extra Wide | Wide |
| 3E（EEE） | Super Wide | Very Wide |
| 4E（EEEE） | Ultra Wide | Extra Wide |
M
M is short for ‘medium,’ and it usually represents a standard width. However, it’s important to note that in the shoe width sizing chart, medium width is not commonly marked with ‘M’ but with ‘B’ or ‘D.’ If you’d like to learn more about what ‘M’ means, you can check out my blog: ‘Shoe Size Guide: What Does M Mean In Shoe Size.’
B
B is typically used for women’s shoes, representing a medium width. If B appears in men’s shoe sizes, it usually indicates a narrow fit. However, it’s important to note that in some cases or with certain brands, B may also be used to represent a medium width in men’s shoes.
Width is Crucial For Finding The Right-fitting Shoes
When choosing shoes, it’s important to find a pair with the right width. Shoes that are too loose or too tight can have an impact on our feet.
Too Tight Shoes
Tight shoes can restrict foot movement and put pressure on the foot, especially the forefoot. The narrow space can cause the big toe to tilt inward, which may lead to issues like bunions or ingrown toenails over time. It can also cause blisters and calluses due to friction and pressure. Additionally, tight shoes may compress blood vessels, leading to numbness and swelling in the feet.
Too Loose Shoes
Too loose shoes can lead to a lack of support and stability while walking. Since they don’t fit the foot properly, they may fail to provide arch support, potentially causing plantar fasciitis. Additionally, insufficient support can increase the strain on the ankles and knees, leading to back pain.
How to Determine Your Shoe Size and Width
Professional Measurement
Many specialty shoe stores or sports brands offer free or paid foot measurement services, using 3D scanners or foot molds to measure foot length, width, and arch height.
DIY Measurement
If you’d like to try measuring your feet yourself, here’s a method you can follow. I’ll guide you step by step on how to measure your feet.
Tools You’ll Need
- A sheet of white paper large enough to fit your entire foot
- A pen
- A measuring tape or ruler
- A flat surface
Draw The Outline
Place the paper on a flat surface, such as your floor or tiles at home. Put on a sock you typically wear and stand on the paper, making sure your heel is against the wall and aligned with the edge of the paper. Keep the pen vertical and trace the outline of your foot.
Measure The Length
Use a measuring tape or ruler to measure the distance from your heel to your longest toe, which is typically either your big toe or second toe. After measuring, record the length.
Measure the width
Measure the width in the same way as the length. The widest part of your foot is usually the ball of your foot. After measuring, record the width.
Other Common Shoe Width Indicators
A
Size A indicates a narrower width, typically ranging from A to 4A. The more A’s, the narrower the shoe. However, narrow widths usually stop at 2A. Sizes 3A and 4A are very rare, and brands offering these sizes are primarily focused on orthotic shoes, medical footwear, and custom-made shoes.
C
Size C falls between B and D, with B and D being the standard sizes for women’s and men’s shoes, respectively. Therefore, size C is slightly wider than the standard width in women’s shoes, but slightly narrower than the standard width in men’s shoes.
D
D represents the standard width for men’s shoes, but in women’s shoes, D indicates a wide width.
E
Size E is considered a wide width for both men’s and women’s shoes, typically suitable for people with wider feet or higher arches.
Differences in Shoe Widths Across Brands
Shoe width standards can vary across brands, so even if the width is labeled the same, the fit can feel different. For example, brands like Nike and ASICS tend to be narrower, while brands like New Balance and Skechers are generally wider. It’s recommended to check the brand’s sizing chart before purchasing to find the best fit for you.
Common Misconceptions About Shoe Width
People With Wide Feet Can Only Choose Shoes One Size Larger
Choosing a larger shoe size doesn’t fully solve the width problem, as it increases both the width and the length. While this can be a solution, it’s better to opt for a wide-width model if available, rather than just going up a size.
All Shoe Models Have Width Options
Actually, not every shoe model offers width options. Many brands’ fashion or casual shoes only provide standard widths. In contrast, athletic shoes and work boots typically offer more width choices.
Conclusion
In short, B and M are important terms in shoe sizing, representing different widths. B is usually associated with women’s widths, while M represents the medium width for both men and women. I hope this article helps you choose comfortable shoes by understanding these terms.
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