Shoe Size Converter — US, UK, EU, JP, CM (with Brand-Fit Notes)
Convert across all 6 standard systems (US Men, US Women, UK, EU, JP/Mondopoint, CM) plus brand-fit notes for Nike, Adidas, Asics — the small-print most converters skip.
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Shoe Size Converter
Brand-fit notes
Each brand has its own quirks vs the Brannock-standard size. Use these offsets when shopping the brand specifically — apply to your converted size, not your usual-pair size in another brand.
| Brand | Offset | Suggested size | Note |
|---|---|---|---|
| Nike | +0.5 | US 9.5 | Most lines run small; size up half. Air Max + Pegasus often true-to-size. |
| Adidas | True | US 9.0 | Standard Brannock fit. Ultraboost runs slightly large. |
| Asics | True (narrow toe) | US 9.0 | Brannock fit, narrower toe box. Wide-foot runners size up half. |
| New Balance | Width-aware | — | Available in B/D/2E/4E. Pick the right WIDTH, don't size up. |
| Brooks | True | US 9.0 | Consistent across running lines. |
| Vans / Converse | +0.5 to +1 | US 9.8 | Skate/canvas runs notoriously small. Size up half to full. |
| Hoka | +0.5 | US 9.5 | Slightly snug; size up half for daily wear. |
| Saucony | True | US 9.0 | Brannock fit; consistent across Endorphin + Triumph lines. |
These offsets are illustrative — specific shoe lines within each brand vary. When in doubt, measure your foot in cm (Mondopoint), convert, and trust the cm number. If between two sizes, size up — too-small is permanent damage, too-large is fixable with insoles.
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What This Converter Does
Convert your shoe size across all 6 standard systems used worldwide: US Men, US Women, UK, EU, JP/Mondopoint, and CM (foot length). Plus brand-fit notes for the most common athletic and casual brands — the small-print most online converters skip.
The canonical unit is CM(Mondopoint = foot length in centimeters). It's the only system where the size NUMBER directly equals a measurable physical dimension. Every other system is derived from CM through a different country's historical convention.
The 6 Systems
- US Men. Brannock-device baseline, 1/3 inch increments, started at the 19th-century US foot-measurement standard. Whole and half sizes.
- US Women. US Men + 1.5. Same physical shoe, different label. A US Men 8 is the same shoe as a US Women 9.5.
- UK.1/3 inch increments from a different starting point than US. UK Men ≈ US Men − 0.5. UK doesn't gender-label sizes; the same number applies regardless of who wears it.
- EU. Paris point (~6.67 mm) increments. Half sizes exist below ~size 45; mostly skipped above.
- JP / Mondopoint. Foot length in cm, 0.5 cm increments. The international standard. Most athletic brands internally use Mondopoint even when they print US/UK on the box.
- CM. Same as JP/Mondopoint. Direct foot length.
How To Measure Your Foot Accurately
- Stand on a piece of paper, weight evenly distributed (foot expands under load — that matters).
- Have someone trace the outline of your foot, or trace it yourself, keeping the pencil perpendicular.
- Measure heel-to-longest-toe in cm. That number is your Mondopoint / JP / CM size directly.
- Add 5-10 mm of toe room for daily wear; less for performance running shoes; more for hiking boots that need thicker socks.
- Repeat for both feet. They typically differ 3-8 mm — size up to fit the larger foot.
Brand-Fit Quirks
Major brands deviate from the Brannock baseline in predictable ways:
- Nike (+0.5 size). Most lines run small; size up half. Air Max + Pegasus exception — usually true-to-Brannock.
- Adidas (true to size). Brannock-standard. Ultraboost runs slightly large; some prefer half-size down.
- Asics (true to size, narrow toe). Brannock length, narrower toe box. Wide-foot runners often size up half a size for toe room.
- New Balance (width-aware).Available in B (narrow), D (standard), 2E, 4E. Don't size up — pick the right WIDTH instead.
- Brooks, Saucony (true). Brannock fit; consistent across running lines.
- Vans / Converse (+0.5 to +1 size). Skate / canvas runs notoriously small. Half to full size up vs your usual.
These offsets are illustrative — specific shoe lines within each brand vary. When in doubt, measure foot length in cm and trust the cm number rather than the size label.
Common Sizing Mistakes
- Sizing down because shoes feel loose new. Athletic shoes pack down 3-5% in the first 50 miles of running; what feels “just barely roomy” in the store is often perfect at 100 miles. If between sizes, size up.
- Confusing size between systems.US 9 in Men is a different physical shoe than US 9 in Women. EU sizing includes neither — it's a single scale. Make sure your size + system pair are consistent before converting.
- Ignoring width.Length + width are independent dimensions. A US Men 9 in D-width is a different shoe than US Men 9 in 2E. If your foot is wide and you wear standard-width shoes, you'll get bunions and arch issues over time. Width-aware brands (New Balance, Brooks) are worth the search.
- Trusting a generic size chart.A “US 9 = EU 42” chart can be off by half a size in either direction depending on the brand. Use a real conversion (this calculator) and the brand's specific size chart together.
How This Differs From Other Converters
The Unit Converter handles general physical dimensions (length, weight, volume, etc.) — use it if you need cm-to-inches without the shoe-specific table lookup. The shoe converter has system-aware logic and brand-fit offsets baked in; the generic unit converter is a pure cm↔inches dimension.
Related Tools
- Unit Converter — general cm/inch/foot conversions for non-shoe contexts.
- Currency Converter — when buying shoes from international retailers.
- Discount Calculator — quick percent-off math at checkout.
Sources & Methodology
The formulas, thresholds, and benchmarks behind this calculator are anchored to the primary sources below. Where a study or agency document is the underlying authority, we link straight to it — not a summary or republished version.
- ISO 9407 — Shoe Sizes: Mondopoint System and Conversions· International Organization for Standardization
International standard defining the Mondopoint system (millimeter foot length and width) and the canonical conversion methodology between regional sizes.
Accessed
- ASTM F539 — Standard Practice for Fitting Athletic Footwear· ASTM International
U.S. standards-body guidance on athletic-footwear fit, last length, and width grading used to validate size-conversion tables.
Accessed
- EN 13402 — Size Designation of Clothes and Footwear (Body Measurements)· European Committee for Standardization
European standard governing footwear sizing nomenclature underpinning EU/UK/US conversion tables used by the calculator.
Accessed
- BSI BS EN 13402 — Size Designation of Footwear (UK Adoption)· British Standards Institution
UK national-body adoption of European footwear sizing standard used as the canonical UK-system reference.
Accessed
- Britannica — Foot Measurement and Shoe Sizing· Encyclopaedia Britannica
Encyclopedia entry on the historical development of regional shoe-sizing systems (Brannock, Paris point, Mondopoint).
Accessed
Frequently Asked Questions
The most common questions we get about this calculator — each answer is kept under 60 words so you can scan.
Why are shoe sizes so inconsistent across countries?
Each system was developed independently. US sizing originated from a 19th-century Brannock device measuring foot length in 1/3 inch increments. UK sizing predates US by 200+ years and uses 1/3 inch increments from a different starting point. European sizing is based on the Paris point (~6.67 mm). Japan and most athletic brands use Mondopoint (foot length in cm), the most physically meaningful unit. CM (foot length) is the only system where the number directly equals a measurable physical dimension.What's the most accurate way to measure my foot?
Trace your foot on paper while standing (your foot expands under load), measure heel to longest toe in cm. Add 5-10 mm of toe room for daily-wear shoes (less for performance running shoes, more for hiking boots). The measured cm is your Mondopoint / JP size; convert to other systems using this calculator. Measure both feet — they typically differ 3-8 mm; size up to the larger foot.How are women's sizes different from men's?
Same physical shoe, different label. US Women = US Men + 1.5 (e.g., a US Men 8 = US Women 9.5). UK and EU don't have a separate gender label — UK 7 is UK 7 regardless of who's wearing it; EU 41 is EU 41. The US convention is mostly historical/marketing. Some brands DO make narrower lasts for women's lines, but the size NUMBER is purely a label, not a different measurement.Why does Nike run small?
Nike's manufacturing baselines reflect Asian foot anatomy from when their production scaled in Asia in the 1980s-90s. Most Nike running shoes (Pegasus, Air Max, Vomero) run roughly half a size smaller than the Brannock measurement. The exception is some Air Force lines which run true. Adidas runs closer to true-to-Brannock; Asics also true-to-size but with a narrower toe box.What about width — does this calculator handle it?
No — width (B/D/2E/4E in US sizing) is a separate dimension. This calculator converts LENGTH only. For width, the Brannock device measures 'arch length' separately. Brands that offer multiple widths: New Balance, Brooks, Saucony (running); Allen Edmonds, Florsheim (dress). If you have a wide foot, picking the right width matters more than picking the right length.How do EU half-sizes work?
EU has half-sizes through ~size 45, then mostly skips half-sizes above (EU 46, 47, 47.5 — but 47.5 is rarer than 47). If your EU size is between two whole sizes, prefer the larger; trying to wedge into the smaller usually creates pressure on the longest toe. CM/JP doesn't have a 'half' concept — sizes are 0.5 cm increments by definition.Why does JP size = my foot length in cm?
JP (and Mondopoint, the international standard JP follows) uses foot length in cm as the size number directly. So if your foot is 26 cm, your JP size is 26. This is the most physically meaningful sizing system — there's no abstraction between 'size' and 'length.' Most athletic brands also use Mondopoint internally even when they print US/UK on the box.How accurate is the conversion at the extremes?
Within ±0.5 size for the typical adult range (US Men 4-13). Sizes above US 14 or below US 4 vary more between brands and the conversion table becomes a rougher approximation. For very large feet (US 15+), check the brand's specific size chart since there's no universal extension rule above the standard table.Can I save scenarios for shopping different brands?
Yes — the URL share captures your size + system, so you can bookmark conversions for repeat shopping. Useful for comparing sizes when buying online from European retailers (eu sizing) or Japanese brands (Mondopoint/cm).What if I'm between two sizes?
Size up. The standard advice from podiatrists and shoe fitters is: shoes too small cause pain and damage (bunions, hammer toes, arch issues over years); shoes slightly large can be fitted with insoles, heel pads, or thicker socks. The 'better safe than sorry' direction is up half a size when you're uncertain.How do I convert kids' shoe sizes?
Kids' US sizing runs separately from adults'. US Kids 13.5 = US Men 1; US Kids 1 = US Men 1.5. EU and CM are continuous from kids to adult — no separate kids' system. This calculator handles adult sizes (US Men 4+); for kids' sizes, measure foot length in cm and use a kids' chart.What about hiking boots vs running shoes vs dress shoes — same conversion?
Same length, different fit advice. Running shoes: half-size up from Brannock (toe room for downhill flexion). Hiking boots: half-size to full-size up + thick socks. Dress shoes: true-to-Brannock (snug heel, no toe room). The calculator gives you length-equivalent sizes; pick the actual NUMBER based on shoe type and brand-fit notes.