US Shoe Size in Inches: Foot Length Chart and How to Convert

by YDA UK

A US shoe size is not a length in inches, but it is tied to one. In the US men’s system, size 1 fits a foot of 7⅔ inches, and every full size adds ⅓ inch. So a foot of 10 inches is a US men’s size 8, and a foot of 11 inches is about a size 10. The catch is that brands apply the system loosely, so the number on the box is a starting point and your measured foot is the real answer.

This guide gives you the formula, a chart with UK, EU and centimetre equivalents, a way to measure at home, and the extra room a shoe needs beyond your foot length. If you or someone you care for has diabetes or a foot condition, read the section on fit and safety carefully.

Ydauk
Find Footwear for Your Measured Fit
Ydauk offers stylish, comfortable footwear with a focus on foot health, for people looking for supportive everyday shoes.
Explore Ydauk footwear

TL;DR

  • US men’s sizing is linear: size 1 is a 7⅔ inch foot, and each full size adds ⅓ inch (each half size adds ⅙ inch).
  • A 10 inch foot is a US men’s 8, which is a UK 7 and about a 40 in EU sizing on most charts.
  • The shoe’s inside must be longer than your foot: aim for roughly 10 to 12 mm (about ½ inch) in front of the longest toe.
  • Charts disagree by a few tenths of an inch, so measure both feet and fit the larger one.
  • If you have diabetes or reduced feeling in your feet, shoes should feel right in the shop. Do not count on breaking them in.

Table of Contents

What a US shoe size actually measures

Shoe sizes are labels, not measurements. The US scale goes back to a simple rule: according to the Brannock Device Company, the system is linear, a men’s size 1 corresponds to a foot 7⅔ inches long, and each size up adds exactly ⅓ inch. Half sizes therefore add ⅙ inch.

That gives you a formula you can do on a phone:

Foot length in inches = 7⅔ + (US men’s size − 1) ÷ 3

Worked examples:

  • US men’s 8: 7.67 + (7 ÷ 3) = 10.0 inches
  • US men’s 10: 7.67 + (9 ÷ 3) = 10.67 inches, so roughly 10⅔ inches
  • US men’s 12: 7.67 + (11 ÷ 3) = 11.33 inches

The same sources add that width grades follow a similar logic, with each width step separated by 3/16 of an inch. Width matters as much as length for comfort, and we come back to it below.

Two cautions. First, this is the theoretical system. Factories build shoes on their own lasts (the foot-shaped forms a shoe is made around), so a size 9 from one brand can feel different from a size 9 from another. Second, women’s and children’s US sizes are offset from men’s, so do not use the men’s formula for them. Use a women’s or kids’ chart, or measure in centimetres or inches and compare with the brand’s own table.

US men’s shoe size in inches: chart with UK, EU and cm

The chart below shows foot length for US men’s sizes 6 to 14, with UK, EU and centimetre equivalents. It is based on a published conversion chart, and it matches the Brannock formula above.

US men’s UK EU Foot length (inches) Foot length (cm)
6 5 38 9.3 23.7
7 6 39 9.7 24.6
7.5 6.5 39 9.8 25.0
8 7 40 10.0 25.4
8.5 7.5 41 10.2 25.8
9 8 41 10.3 26.2
9.5 8.5 42 10.5 26.7
10 9 43 10.7 27.1
10.5 9.5 43 10.8 27.5
11 10 44 11.0 27.9
12 11 45 11.3 28.8
13 12 46 11.7 29.6
14 13 48 12.0 30.5

How to read it: find your foot length in inches in the fourth column, then move left to your US size. Foot length falls between two rows? Choose the longer row, never the shorter.

Why you will see slightly different numbers elsewhere

Other charts round differently or shift by half a size. One converter, for example, lists a US men’s 8 at 10.2 inches and a UK 7.5, where the chart above puts it at 10.0 inches and a UK 7. A difference of 0.2 inch is about 5 mm, which is easily enough to change how a shoe feels.

Two US 8 chart readings compared in inches

This is not an error so much as a symptom. According to the ISO standard on this subject, shoe size is a manufacturer’s label, and the only objective way to match foot to shoe is Mondopoint, a system based on foot length in millimetres. If a brand prints a foot length in its size guide, trust that over any general chart.

The UK to US shortcut for men

For men’s sizes, the US number is generally one higher than the UK number in the chart above (UK 7 is US 8). Brands do not all follow this, so treat it as a quick check rather than a rule. Women’s sizes use a different offset, so take those from a women’s table. Our own US shoe size chart and conversion guide and men’s foot size chart go through the UK, EU and US pairings in more detail.

How to measure your foot in inches at home

You only need a sheet of paper, a pen, a ruler or tape marked in inches and centimetres, and a wall.

  1. Measure in the evening. Feet tend to be larger later in the day, so an evening measurement is the safer one.
  2. Stand on the paper with your heel against the wall. Wear the type of sock you will wear with the shoes.
  3. Mark the tip of your longest toe. That is not always the big toe. Keep your weight evenly spread, and ask someone to help if you can.
  4. Measure from the wall edge to the mark in inches and in millimetres.
  5. Repeat with the other foot. If one is longer or wider, use the bigger number.
  6. Find that length in the chart, or in the brand’s own size guide.

The Brannock device that shoe shops use has an extra step worth copying. It reads two lengths, heel to toe and heel to ball of the foot. According to its fitting instructions, if the two readings point to different sizes, you fit to the larger one so the shoe flexes where your foot does. At home, you can approximate the ball measurement by marking the ball joint on the paper too and comparing with the brand’s guidance.

For a fuller walk-through with photographs, see our guides to measuring your foot size at home and measuring your foot correctly, or the seven-step podiatrist-aligned method.

Get measured every time you buy

Feet change with age, weight and swelling. Harvard Health advises having both feet measured every time you buy new shoes, and buying for the larger foot if they differ. Last year’s size may not be this year’s.

Your foot length is not your shoe length

This is where most online buyers go wrong. A 10 inch foot does not fit comfortably in a shoe with a 10 inch inside. Your foot moves forward as you walk, and the toes need space.

NHS guidance gives a clear target. A Scottish NHS patient guide says there should be around 10 mm between the end of your longest toe and the end of the shoe, and East Lancashire Hospitals NHS Trust puts it as a 12 mm (½ inch) gap in standing. So aim for 10 to 12 mm, a little under half an inch.

In practice, that means:

  • A 10 inch (25.4 cm) foot needs an internal shoe length of about 10.4 to 10.5 inches (roughly 26.5 cm).
  • That is why the chart’s size 8 is a foot of 10 inches, while the shoe itself is longer than that.
  • If a brand lists the insole or internal length, compare it with your foot length plus 10 to 12 mm.

The insole test

Practitioners suggest a simple check that does not rely on any label. Take out the shoe’s removable insole, stand on it, and look at the space in front of your longest toe and at the sides. NHS guidance on diabetic footwear recommends the same trick, as East Lancashire Hospitals NHS Trust describes. If your foot spills over the edge of the insole, the shoe is too narrow however correct the size label looks.

Customer checking foot space on a removed insole

Width and depth

Length in inches is only one dimension. The same NHS leaflet lists good width across the widest part of the foot and enough depth in the toe box, and says to avoid pointed toes. Wide fittings may suit some feet better. A shoe that matches your length but pinches across the ball is the wrong shoe.

Fit and safety for diabetes and foot conditions

If you have diabetes, neuropathy or a foot deformity, a badly fitting shoe is a medical risk rather than a comfort problem. The advice below comes from NHS podiatry sources. Your own podiatrist or diabetes foot protection team should confirm what suits your feet.

  • Do not plan to break shoes in. A clinical resource from LSU Health’s diabetic foot programme calls breaking-in a dangerous myth for people who have lost protective sensation. Shoes should feel comfortable when you buy them, and any early rubbing or pressure point is a warning.
  • Try on both shoes. NHS Greater Manchester diabetes guidance notes that most people’s feet are slightly different sizes, so always try on both.
  • Keep heels low. Oxford Health NHS Foundation Trust advice points to a heel height of no more than 2.5 to 3 cm, roughly 1 to 1.2 inches, because higher heels shift weight to the forefoot and raise pressure.
  • Check the inside. Run your hand inside each shoe for seams or rough spots before you put your foot in.

If you notice redness, a blister or any broken skin after wearing new shoes, stop wearing them and contact your podiatrist or GP promptly. If you are unsure whether your size has changed, ask your podiatry or diabetes team to measure you. Our guides on choosing diabetic footwear and diabetic footwear tips cover the practical side.

Our view on sizes in inches

We sell shoes built around foot health, so we spend a lot of time on the gap between a size label and a real foot. Here is how we see it.

A chart is useful because it gets you into the right neighbourhood. It cannot tell you how a particular last treats your toes or how much volume the upper has. That is why we point readers to measurement first, then conversion, and not to a size they happen to have worn for ten years.

Our footwear uses proprietary YDA technology designed to stabilise and assist each step, with comfort, style and energy efficiency for everyday wear in mind. Whenever someone is buying shoes online, though, the process should be the same whatever the brand: measure both feet, add the toe room, check width, and compare with the brand’s own guide. If your measurement lands between two sizes, we would choose the size that leaves room, not the one that merely fits on paper.

Our honest advice for anyone with problem feet is to treat the fit rules above as non-negotiable and to involve a podiatrist where a condition is involved.

— Panagiotis

Choosing shoes once you know your size

Once you have a number, the shopping checklist is short:

  1. Convert your longest foot length into a size using the chart or the brand’s own table.
  2. Add 10 to 12 mm of internal length beyond the foot.
  3. Check the toe box shape: round or square, with room for toes to spread.
  4. Stand up in the shoes (or, online, check the return terms) and walk a few steps.
  5. Reassess later in the day if your feet swell.

If you want shoes designed around foot health, you can browse our high performance footwear. The technology behind YDA shoes explains how they support each step. Stock changes often, so check availability before you plan a purchase.

For other size systems, our shoe conversion chart, our guide to a 10 inch foot as a US men’s 8 and our home measuring guide go deeper.

FAQ

How many inches is a US size 10 shoe?

A US men’s size 10 corresponds to a foot of about 10.7 inches (roughly 27.1 cm) on the chart above. The shoe’s inside needs to be longer than that, by around 10 to 12 mm. Other charts may show slightly different figures, so check the brand’s own guide.

Is shoe size the length of the shoe in inches?

No. Size is a label, and the shoe’s outside and inside lengths are both longer than the foot it fits. In the US system the size is tied to foot length by a fixed step of ⅓ inch per full size, according to Brannock, but brands use different lasts, so the same size can vary.

What is a 10 inch foot in US shoe size?

A foot of 10 inches is a US men’s size 8, which is a UK 7 in the chart above. If you are measuring a women’s foot, use a women’s chart, as the offset differs from men’s sizing.

Which foot should I measure?

Both. Most people’s feet differ slightly, and Harvard Health advises buying for the larger or wider foot. Do it each time you buy, because size can change over the years.

Sources

Back to Blog