How do I measure my shoe size at home?

To measure your shoe size at home, place your foot on a piece of paper and trace the outline. Mark the heel and the tip of the longest toe, then measure the distance between these two points in centimetres. Use this foot length value in a shoe size conversion chart or calculator. Measure both feet and use the larger measurement. For best accuracy, measure in the afternoon when feet are at their largest.

What is a European size 42 in US sizing?

A European size 42 corresponds to approximately US men's size 8.5 and US women's size 10. EU size 42 is designed for a foot length of approximately 26.5 to 27 centimetres. The exact correspondence varies slightly by brand because EU sizing is not perfectly standardised across all shoe manufacturers, so checking the brand's specific size chart is advisable.

What is the difference between US men's and US women's shoe sizes?

For the same foot length, US women's shoe sizes are approximately 1.5 sizes larger than US men's sizes. A foot length of 26 cm corresponds to US men's size 8 and US women's size 9.5. This means a woman wearing US women's size 8 can often wear a US men's size 6.5 in styles designed for men, which is useful for accessing wider size availability or different style options.

How do I convert UK shoe size to US size?

To convert UK shoe size to US men's size, add 0.5. A UK size 8 equals US men's size 8.5. To convert UK to US women's size, add 2. A UK size 6 equals US women's size 8. European to US conversion is less consistent by brand but a rough guide is: EU size minus 33 gives approximate US men's size, and EU size minus 31 gives approximate US women's size.

What is Japanese shoe sizing?

Japanese shoe sizing uses the foot length in centimetres as the size number. A Japanese shoe size of 26.5 is designed for a foot 26.5 centimetres long. This is the most intuitive system for direct conversion from measurement and eliminates the regional variation that affects US, UK, and EU sizing. Japanese sizes are used by several international brands alongside their other size labels.

What shoe size is 26 cm?

A foot length of 26 centimetres corresponds to approximately US men's size 8, US women's size 9.5, UK size 7, and European size 40 to 41. In Japanese sizing, a foot of 26 cm is simply size 26. Minor variations exist between brands, so using the brand-specific size chart alongside this general conversion is recommended.

How much space should there be between my toes and the end of my shoe?

There should be approximately 1 to 1.5 centimetres (about the width of your thumb) between the tip of your longest toe and the end of the shoe. This clearance is called the toe box allowance and is essential for comfort during walking, preventing blisters, nail damage, and bunion formation. A shoe that fits perfectly when standing may feel tight when walking if it lacks sufficient toe box clearance.

Why do shoe sizes vary between brands?

Shoe sizes are not perfectly standardised across manufacturers. Different brands use different lasts (the foot-shaped moulds around which shoes are constructed), which results in variation in actual shoe length and width at the same nominal size. A size 10 from one brand may be 0.5 to 1 centimetre longer than a size 10 from another. For this reason, always refer to the brand's specific size chart and, when possible, try on or consult customer reviews mentioning whether the shoe runs large or small.

What is a wide shoe width?

In the US sizing system, shoe width is indicated by a letter code: B is standard (medium) for women, D is standard for men. E or EE indicates wide, and 2E (EE) or 4E (EEEE) indicate extra wide. A and AA are narrow widths. Many shoes are sold in standard width only; specialist wide-width shoes are available from brands that cater to wider feet. In Europe, width is less commonly standardised in retail sizing and is instead addressed through last selection.

How do I know if my shoes are too small?

Signs that your shoes are too small include numbness or tingling in the toes after an hour of wear, visible red marks or blisters on the sides or top of the toes, the longest toe pressing against the shoe cap, the shoe creasing heavily across the vamp, or difficulty putting the shoe on without a shoehorn. Shoes should feel snug at the heel and midfoot but never tight across the toes or the ball of the foot when properly sized.

Shoe Size Calculator – US, UK, EU and JP Shoe Sizes

Shoe Size Calculator

The Shoe Size Calculator converts your foot length in centimetres or inches into shoe sizes across US men's, US women's, UK, European, and Japanese sizing systems. It also provides guidance on measuring your foot correctly for the most accurate result. Use it to buy shoes online, convert between international size systems, and confirm your size before purchasing from unfamiliar brands or countries.

System	Size
US	9.5
UK	9
EU	43
Japan (mm)	265
Foot length	26.0 cm / 10.2 in

System

Size

9.5

Japan (mm)

265

Foot length

26.0 cm / 10.2 in

What Is the Shoe Size Calculator?

The Shoe Size Calculator converts your foot length in centimetres into shoe sizes across US men's, US women's, UK, European, and Japanese sizing systems simultaneously. Online shoppers, travellers purchasing shoes abroad, and parents buying children's shoes use it to work out the correct size without needing to try on a shoe first. Unlike clothing sizes, shoe size systems are more directly tied to a physical measurement (foot length), but the conversion formulas differ across regions, and a given numeric size does not represent the same absolute shoe length in every country. According to the ASTM E1767 standard on footwear sizing, foot length measured in centimetres is the most reliable basis for all shoe size determinations, regardless of which regional size system a consumer eventually uses.

The most common cause of shoe buying errors is relying on a remembered size from one brand or one size system when buying from another. A person who wears US size 10 in American athletic shoes may find that the same labelled size in a European brand runs half a size smaller or larger due to differences in last construction and the underlying sizing formula. Given that feet also change size slightly across the day (swelling by up to half a centimetre from morning to evening), measuring in the afternoon and using the larger of the two feet provides the most reliable input for the calculator.

How Shoe Size Systems Work

Every major shoe sizing system attempts to map foot length to a size number, but with different scales and offsets. US men's sizing adds approximately 1.5 to the foot length in inches measured from heel to toe, relative to an antique Paris Point scale. US women's sizes run 1.5 sizes larger than men's for the same foot length. UK sizes use the same scale as US men's but are approximately 0.5 sizes smaller (a UK 9 equals a US men's 9.5). European sizes use a unit called the Paris Point (one-third of a centimetre), so EU size equals foot length in centimetres divided by 0.667, approximately: a 27 cm foot gives an EU size of about 40 to 41. Japanese sizing uses centimetres directly, making it the simplest for metric users: a 26 cm foot is Japanese size 26.

These formulas involve rounding conventions that cause the conversion to be approximate rather than exact. The ISO 19407 footwear sizing standard attempts to harmonise these systems, but adoption among manufacturers is incomplete, and in practice brand-level variation within each system is as large as the inter-system variation for sizes that fall near the boundary between two numbers. That said, knowing the conversion formula allows you to identify the nearest size and then verify with the brand's specific chart before purchasing.

Shoe Size Conversion Reference Table

The table below shows common foot lengths and their approximate equivalent sizes across the four main systems. Small variations between brands are normal; treat these as starting points rather than exact guarantees.

Foot Length (cm)	US Men's	US Women's	UK	EU (approx.)
24.5	6.5	8	6	38 to 39
25.5	7.5	9	7	40
26.5	8.5	10	8	42
27.5	9.5	11	9	43
28.5	10.5	12	10	44 to 45
29.5	11.5	13	11	46
30.5	12.5	14	12	47

Width, Toe Box, and Fit Beyond Length

Shoe size is fundamentally a length measurement, but foot width, arch height, and toe shape affect how a shoe fits beyond the number on the label. In the US system, width is coded by letters: B is standard width for women, D is standard for men, E or EE is wide, and AA or A is narrow. A person with wide feet who selects the correct length size but the wrong width may find the shoe is too tight across the ball of the foot, causing blisters, bunions, and discomfort, even though the length is correct. Many casual and fashion shoes are sold in standard width only, and individuals with notably wide or narrow feet benefit from seeking brands that offer multiple width options.

The toe box clearance is equally important. There should be approximately 1 to 1.5 centimetres of space between the tip of the longest toe and the end of the shoe interior when standing. Shoes that fit correctly when sitting may feel tight when walking or running because the foot slides forward under load. The American College of Foot and Ankle Surgeons shoe fitting guidelines recommend standing in both shoes and walking several steps before assessing fit, and advise against buying shoes that require breaking in to fit comfortably, as this usually indicates the shoe is too small in one or more dimensions.

Accuracy and Limitations

The shoe size calculator is accurate for the foot length entered using the standard conversion formulas. Its real-world accuracy is limited by brand-to-brand variation in the actual shoe length manufactured at a given nominal size. Studies of shoe sizing consistency across brands have found variation of up to one full size (approximately 8 millimetres) between the shortest and longest shoe labelled with the same size number from different manufacturers. The calculator identifies the most likely correct size and size range, but the brand's specific size chart and customer reviews mentioning fit consistency are the most reliable additional data sources when buying online.

The tool does not account for foot shape beyond length: high arches, low arches, wide toes, or bunions may make a shoe that fits in length uncomfortable at the width or instep. It also does not account for sock thickness: a shoe that fits over a thin athletic sock will be too tight with a thick wool hiking sock. For outdoor and performance footwear, measuring the foot with the type of sock to be worn during use is the best practice.

The Most Common Shoe Sizing Mistake

The mistake I see most often is using a shoe size from one brand or one country as the reference when buying from a different system, without doing the conversion. A person who wears US women's size 8 buying shoes labelled EU size 38 will be half a size too small: EU 38 equals US women's 7.5, not 8. With that in mind, always convert from your foot length in centimetres to the target system's size number using the calculator, rather than transferring a size number directly across systems. This mistake is most common when travellers buy shoes in Europe, Japan, or the UK using a remembered US size, and arrive home to find a shoe that is half a size off in a system where the numbers look similar but represent slightly different absolute lengths.

Shoe Size Calculator