Free Shoe Size Converter - US, UK, EU, CM Size Charts

About This Tool

The Shoe Size Converter lets you convert shoe sizes between US, UK, EU, and other international sizing systems. a professional, student, or hobbyist, this tool is save you time and deliver accurate results without requiring any downloads or sign-ups.

by Michael Lip. Shoe Size Converter is designed for offline-capable use. Once loaded, it needs no internet connection and sends zero data to any external service.

Original Research: Shoe Size Converter Industry Data

I compiled this data from web analytics for top conversion sites, published NIST outreach reports on metric adoption, and annual digital tool usage surveys. Last updated March 2026.

Source: WorldData.info reports, Wolfram Alpha analytics, and unit conversion usage studies. Last updated March 2026.

Understanding Shoe Size Systems Worldwide

Shoe sizing is far more complex than most consumers realize, with multiple sizing systems in use around the world that evolved independently and do not convert neatly to one another. The most widely used systems include US sizing, UK sizing, European (EU or Continental) sizing, and the Mondopoint system used primarily in military, industrial, and athletic footwear. US and UK sizes are both based on inch measurements but use different starting points and increments, resulting in approximately a one to one-and-a-half size offset between the two systems. European sizes use the Paris Point system, where each size increment equals approximately 6.67 millimeters (two-thirds of a centimeter).

The Mondopoint system, established by the International Organization for Standardization (ISO 9407), represents the most rational approach to shoe sizing because it measures the foot in millimeters of both length and width. A Mondopoint size of 265/100 means the shoe is designed for a foot that is 265 millimeters long and 100 millimeters wide. While Mondopoint has not gained widespread adoption in consumer retail, it is used in military procurement (NATO specifies shoe sizes in Mondopoint), industrial safety footwear, and some athletic brands. The precision of Mondopoint eliminates much of the ambiguity inherent in the traditional sizing systems and provides a universal reference for converting between them.

Adding further complexity to shoe size conversion is the inconsistency among manufacturers. A size 10 from one brand may fit very differently from a size 10 in another brand, even within the same sizing system. This variation arises from differences in last shapes (the three-dimensional forms around which shoes are constructed), design intent (some brands size generously while others run narrow), and regional market conventions. Width designations also vary, with the US system using letters from AAA (narrowest) through EEE (widest), while European sizing typically does not specify width. Online shoe size converters provide valuable guidance, but trying shoes on or consulting brand-specific size guides remains the most reliable way to ensure a proper fit.

Practical Applications of Shoe Size Conversion

International online shopping has made shoe size conversion an everyday necessity for millions of consumers. When purchasing shoes from a retailer or brand based in another country, accurately converting your size from your home system to the seller's system is essential to avoid the cost and inconvenience of returns. A customer in the United States ordering from a European retailer needs to know that their US men's size 10 corresponds approximately to an EU 43, while a UK shopper ordering from an American brand needs to know that their UK 8 is roughly a US 8.5. Online converters and brand-specific size charts help bridge this gap, but the variability between manufacturers means that these conversions should be treated as starting points rather than guarantees.

Shoe size conversion is also critical in the footwear industry itself, where manufacturers, distributors, and retailers must accurately label and market products across multiple markets. A shoe factory producing footwear for global distribution must apply correct size labels in US, UK, EU, and sometimes additional regional systems for each pair produced. Errors in size conversion at the manufacturing or labeling stage can result in costly returns, customer dissatisfaction, and damage to brand reputation. Quality control processes in the footwear industry include systematic verification of size conversions against established reference charts and physical measurement standards.

Athletic organizations, military services, and employers that provide footwear to their members or employees rely on accurate size conversion tables for procurement and distribution. Military forces operating in multinational coalitions must reconcile sizing across different national standards when issuing shared equipment. Sports teams outfitting international players need to convert sizes reliably to ensure proper fit and prevent injuries. Large employers providing safety footwear to their workforce may source shoes from multiple countries and must ensure consistent sizing across their inventory. In all these contexts, a reliable and comprehensive shoe size converter is an essential operational tool.

Tips and Best Practices for Finding the Right Shoe Size

Measure your feet at the end of the day when they are at their largest due to natural swelling that occurs throughout the day. Stand on a piece of paper, trace the outline of each foot, and measure the longest point from heel to toe and the widest point across the ball of the foot. Compare these measurements in millimeters or inches against the size charts provided by the specific brand you are considering. Because your two feet are often slightly different sizes, always base your shoe size on the larger foot. Having an accurate measurement in centimeters or millimeters allows you to use any conversion chart with confidence.

When shopping internationally, rely on the specific brand's size chart rather than generic conversion tables. Most reputable footwear brands publish detailed size guides on their websites that map their sizes to actual foot measurements in centimeters. These brand-specific charts account for the particular last shapes and fit characteristics of that brand's products, making them more reliable than generic conversion tools. If a brand provides measurements for both foot length and width, use both dimensions to select the optimal size. Reading customer reviews that mention fit (runs large, runs small, narrow, wide) provides additional valuable information for making your selection.

Consider the type of sock or hosiery you will wear with the shoes when determining size. Thick athletic socks, winter wool socks, and orthotic insoles all take up space inside the shoe and may require sizing up by a half to a full size compared to thin dress socks or bare feet. If you plan to use custom orthotics, bring them with you when trying on shoes in a store, or order a half size larger than your measured foot size when shopping online. The goal is to have approximately a thumb's width of space between the longest toe and the front of the shoe, with the widest part of the foot sitting comfortably at the widest part of the shoe without pinching or excessive looseness.

Common Mistakes to Avoid in Shoe Size Conversion

The most common mistake is assuming that shoe sizes are standardized and universal. A size 42 from an Italian luxury brand may fit very differently from a size 42 from a German comfort shoe manufacturer, even though both use the European sizing system. The EU size 42 technically corresponds to a foot length of approximately 263 millimeters based on the Paris Point formula, but individual brands may apply their own fitting allowances and last shapes that alter the internal dimensions of the shoe. Always check the brand's specific size chart and, when possible, read reviews from customers who have purchased the same model to understand how it fits in practice.

Another frequent error is using outdated or inaccurate conversion charts found on various websites. The internet is filled with shoe size conversion tables that contain errors, particularly at the extremes of the size range and for less common sizing systems such as Japanese, Korean, and Brazilian sizes. Cross-reference conversions across at least two or three reputable sources before making a purchase. The most reliable references include the brand's own website, established international retailers that have verified their conversion charts through extensive sales data, and standardized references based on ISO or national measurement standards.

People also commonly make the mistake of ignoring width when converting shoe sizes. While the US sizing system includes width designations (B for standard women's, D for standard men's, with narrower and wider options available), the European and UK systems generally do not. A person who wears a US 10 Wide (2E) cannot simply look up the standard conversion to EU 43 and expect a proper fit, because the European shoe at that size may not accommodate a wider foot. Some European brands offer width options designated as G, H, or K for wider fits, but these are not standardized across the industry. If you have particularly narrow or wide feet, seeking out brands that specifically cater to non-standard widths or offer Mondopoint sizing is advisable.

Industry Standards and References for Footwear Sizing

The footwear industry operates under several international and national standards that govern sizing, labeling, and measurement. ISO 9407 (Shoe sizes - Mondopoint system of sizing and marking) establishes the Mondopoint standard as the international reference for shoe sizing. The European Committee for Standardization (CEN) has published EN 13402 for garment sizing that includes provisions for footwear. In the United States, the American National Standards Institute (ANSI) and the American Society for Testing and Materials (ASTM) have published standards related to footwear measurement and labeling. Despite these standards, the absence of a universally enforced mandatory sizing system means that significant variation persists in practice across brands and markets.

The Brannock Device, invented by Charles Brannock in 1927, remains the most widely used foot measurement tool in North American shoe retail. This mechanical device measures foot length, arch length, and width simultaneously, providing a comprehensive assessment of foot dimensions for sizing purposes. While digital scanning technology has emerged as a more precise alternative, the Brannock Device continues to be the standard in most brick-and-mortar shoe stores due to its simplicity, durability, and low cost. Online retailers have developed their own measurement guides and sometimes ship measurement tools to customers, but the accuracy of self-measurement inevitably introduces more variability than in-store measurement by a trained fitter.

Advancements in three-dimensional foot scanning technology are beginning to transform the footwear industry's approach to sizing. Companies like Volumental, FitStation by HP, and AiFoot offer scanning solutions that capture detailed three-dimensional models of the foot, enabling more precise size recommendations that account for foot shape in addition to simple length and width measurements. Some retailers have installed in-store scanning kiosks, while others offer smartphone-based scanning apps that use the phone's camera to create a three-dimensional foot model. As these technologies mature and gain wider adoption, they promise to significantly reduce the rate of returns due to sizing issues, which currently represents a major cost for the footwear industry and a source of frustration for consumers.

Understanding Children's Shoe Size Conversion

Converting children's shoe sizes between international systems introduces additional complexity because children's sizing scales are distinct from adult scales and the transition points between children's and adult sizes vary by system. In the US system, children's sizes run from 0 (newborn) through 13.5, after which the scale resets to 1 for youth or junior sizes that overlap with the lower end of the adult scale. The UK system follows a similar but not identical pattern, while the European system uses a continuous numerical scale from approximately size 15 for infants through size 49 for large adult feet, without the reset that characterizes the US and UK systems.

Children's feet grow rapidly, particularly during the first three years of life and again during adolescence. Pediatric podiatrists recommend checking shoe fit every two to three months for toddlers and every four to six months for school-age children. A child's shoe should have approximately one thumb's width (about 12 millimeters) of space between the longest toe and the end of the shoe to allow for growth. Purchasing shoes that are too large in anticipation of growth is counterproductive, as oversized shoes can cause tripping, blisters, and abnormal gait patterns that may affect foot development. Online shoe size calculators that incorporate the child's age and current foot measurement can help parents estimate when the next size upgrade will be needed.

The variability between manufacturers is often even more pronounced in children's footwear than in adult shoes. Some brands size children's shoes generously to extend the wearable period, while others size more precisely. Width options, which are important for growing feet, are less commonly available in children's shoes than in adult shoes. Parents purchasing children's shoes from international brands should pay particular attention to the specific brand's size chart rather than relying on generic conversion tables, and should consider brands that offer wider size ranges. Investing in properly fitting shoes during childhood is important for long-term foot health, as the bones of the foot are still forming and are susceptible to deformation from poorly fitting footwear.