Shoe Size Converter & Conversion Chart

Shoe size conversions are recommendations, not exact unit conversions: a size number is a marking convention, so US, UK, EU and Asian sizes only relate to each other through the foot the shoe is built for. This converter goes size to foot length to size, and shows the range and the source behind every answer.

Read this first. Shoe sizes are marking conventions, not units. Nothing here is converted by adding a number to your size: every answer goes through the foot length the size designates, and every answer shows the range and the source behind it. Only the millimetre, centimetre and inch results on this page are exact.

JavaScript is off in this browser. The default conversion shown alongside (US Men's 10 to EU) is precomputed with the same engine, and every conversion chart on this page is server-rendered, so you can read any size off the tables without scripting. Changing the controls live needs JavaScript.

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Who is this for?

Convert a size

From

Size Sizes come from the canonical catalog for the system and population you picked — nothing outside the published ladder is offered.

Result

Closest matchEU 43No adjacent size overlaps this foot-length interval.

Foot-length reference 271 mm · 27.1 cm · 10.67 in (interval 269–273 mm)

Result type Source-dependent sizing guideline — not an exact unit conversion

Moderate agreement One side is a last-length ladder bridged by the disclosed allowance interval, so published charts differ by up to half a size.

Brands differ. Sizing systems describe the foot; a shoe describes a last. Two brands can mark the same number and fit differently, so treat this as a starting point and check the manufacturer’s own chart for the model you are buying.

Source

The Brannock Device Company (Liverpool, New York) — The Brannock Device® foot-measuring scale — the US retail foot-measuring standard Tier 2 · reference-only · reviewed 2026-08-09
Public-domain historical construction — Continental European Paris point — Paris point last-length progression (1 Paris point = 2/3 centimetre) Tier 3 · public-domain-rule · reviewed 2026-08-09
CalcDomain (own work, fully disclosed) — Last-length to foot-length allowance interval used to bridge the UK and EU ladders Tier 3 · own-work · reviewed 2026-08-09

Why this result?

Input: Men's (adult) · US Men's 10.
US Men's rule — Foot length (inches) = (size + 22) ÷ 3 — the Brannock scale anchors men’s size 1 at a 7 2/3 inch foot and adds 1/3 inch (one barleycorn) per full size.
Foot-length reference: 271 mm (published interval 269–273 mm).
EU rule — Last length (mm) = size × 20 ÷ 3 (one Paris point = 2/3 cm); foot length = last length − allowance.
Target interval search: 1 EU size(s) overlap that interval (43).
Closest EU size: 43 (nominal 272 mm, 1 mm from the reference).

Calculation receipt

Question: What is US Men's 10 in EU sizes (Men's (adult))?
Input: US Men's 10 (Men's (adult))
Population: Men's (adult)
Source system: US Men's
Source size: 10
Reference foot length: 271 mm · 27.1 cm · 10.67 in
Target system: EU
Closest target: EU 43
Alternative / observed range: 43
Method: Size → foot-length reference → target sizing system. No size-to-size arithmetic is used at any point. The closest match is the target record whose nominal foot length is nearest the reference; every target record whose interval overlaps the source interval is reported as the observed range.
Formula: target size = the EU record whose nominal foot length is closest to the US Men's reference foot length
Substitution: US Men's 10 → 271 mm → EU 43
Steps: Input: Men's (adult) · US Men's 10.
US Men's rule — Foot length (inches) = (size + 22) ÷ 3 — the Brannock scale anchors men’s size 1 at a 7 2/3 inch foot and adds 1/3 inch (one barleycorn) per full size.
Foot-length reference: 271 mm (published interval 269–273 mm).
EU rule — Last length (mm) = size × 20 ÷ 3 (one Paris point = 2/3 cm); foot length = last length − allowance.
Target interval search: 1 EU size(s) overlap that interval (43).
Closest EU size: 43 (nominal 272 mm, 1 mm from the reference).
Source dataset: shoe-size-catalog v1.0.0
Source / dataset version: brannock-device · brannock-scale-rule@1.0.0
Result status: Source-dependent sizing guideline — not an exact unit conversion
Check (passed): Granularity check: the chosen EU size maps back to 272 mm, 1 mm from the source reference (tolerance 8.5 mm = one full size of the coarser system). This re-enters the same catalog, so it is a self-consistency check, not independent verification.
Precision: Foot-length reference rounded to whole millimetres.
Engine: shoe-size-engine v1.0.0 · receipt 1.0.0

Quick shoe size conversion chart

Rows are the measurement itself, which is what “what shoe size is 26 cm?” actually asks. Read across from your foot length to the system you need. Sizes shown are the closest published size in each system; the full charts below list every size and its reference length.

Adult foot length to shoe size — every figure generated by the shoe-size engine from the canonical catalog
Foot length (mm)	Foot length (cm)	Foot length (in)	US Men's	UK	EU	Mondopoint	Japan (JP)	China (CN)	Korea (KR)
220	22.0	8.66	4	2.5	35	220	22	220	220
225	22.5	8.86	4.5	3.5	36	225	22.5	225	225
230	23.0	9.06	5	4	37	230	23	230	230
235	23.5	9.25	5.5	4.5	37	235	23.5	235	235
240	24.0	9.45	6.5	5	38	240	24	240	240
245	24.5	9.65	7	5.5	39	245	24.5	245	245
250	25.0	9.84	7.5	6.5	40	250	25	250	250
255	25.5	10.04	8	7	40	255	25.5	255	255
260	26.0	10.24	8.5	7.5	41	260	26	260	260
265	26.5	10.43	9.5	8	42	265	26.5	265	265
270	27.0	10.63	10	8.5	43	270	27	270	270
275	27.5	10.83	10.5	9	43	275	27.5	275	275
280	28.0	11.02	11	10	44	280	28	280	280
285	28.5	11.22	11.5	10.5	45	285	28.5	285	285
290	29.0	11.42	12	11	46	290	29	290	290
295	29.5	11.61	13	11.5	46	295	29.5	295	295
300	30.0	11.81	13.5	12	47	300	30	300	300

How to measure your foot for shoe size

Every conversion on this page is anchored to one number: the length of your foot in millimetres. Getting that number right matters more than the system you convert into — a whole size is only about 8.5 mm, so a 5 mm reading error is already more than half a size.

Foot length is the straight-line distance from the back of the heel to the tip of the longest toe — which is not always the big toe. Width is a separate measurement across the ball of the foot and does not change your length size.

Measure both feet. Most people have feet of different lengths, and the difference is often enough to cross a half-size boundary.
Use the longer foot. Size to the bigger one and adjust the fit of the other shoe with lacing or an insole. Sizing to the smaller foot guarantees one shoe is too short.
Measure in millimetres. Stand on a sheet of paper with your heel against a wall, mark the tip of the longest toe, and measure the distance in millimetres. Whole millimetres beat rounded centimetres, and this converter accepts mm, cm or inches.
Do not confuse foot length with shoe length. A shoe last is longer than the foot inside it. Measuring the insole of a shoe you already own gives the last length, not your foot length, and will size you up by a size or more.
Check the manufacturer chart before you buy. A converted size tells you which number is built for your foot; only the brand's own chart tells you what that brand does with the number.

Measure standing with your weight on the foot, and preferably at the end of the day when feet are at their largest. A foot spreads under load: a seated measurement can read several millimetres short.

Men's shoe size conversion chart

Driven by the US Men's ladder so every US size appears, with the foot length each one designates and the closest size in every other supported system. Generated by the shoe-size engine from the canonical catalog — there is no separately maintained table to drift.

Men's shoe size conversion chart — generated from the canonical shoe-size catalog
Foot length (cm)	Foot length (in)	US Men's	UK	EU	Mondopoint	Japan (JP)	China (CN)	Korea (KR)
21.6	8.50	3.5	2.5	35	215	21.5	215	215
22.0	8.66	4	2.5	35	220	22	220	220
22.4	8.82	4.5	3	36	225	22.5	225	225
22.9	9.02	5	4	37	230	23	230	230
23.3	9.17	5.5	4	37	235	23.5	235	235
23.7	9.33	6	4.5	38	235	23.5	235	235
24.1	9.49	6.5	5	38	240	24	240	240
24.6	9.69	7	6	39	245	24.5	245	245
25.0	9.84	7.5	6.5	40	250	25	250	250
25.4	10.00	8	6.5	40	255	25.5	255	255
25.8	10.16	8.5	7	41	260	26	260	260
26.2	10.31	9	7.5	42	260	26	260	260
26.7	10.51	9.5	8.5	42	265	26.5	265	265
27.1	10.67	10	8.5	43	270	27	270	270
27.5	10.83	10.5	9	43	275	27.5	275	275
27.9	10.98	11	9.5	44	280	28	280	280
28.4	11.18	11.5	10.5	45	285	28.5	285	285
28.8	11.34	12	10.5	45	290	29	290	290
29.2	11.50	12.5	11	46	290	29	290	290
29.6	11.65	13	11.5	47	295	29.5	295	295
30.1	11.85	13.5	12.5	47	300	30	300	300
30.5	12.01	14	12.5	48	305	30.5	305	305
30.9	12.17	14.5	13	49	310	31	310	310
31.3	12.32	15	13.5	49	315	31.5	315	315
31.8	12.52	15.5	14.5	50	320	32	320	320
32.2	12.68	16	15	—	320	32	320	320

Women's shoe size conversion chart

Driven by the US Women's ladder. Remember that the US women's scale is the one place where sources genuinely disagree — the measuring device offsets it by one size from the men's scale, most retail charts by one and a half — so read the converter's observed range alongside this table.

Women's shoe size conversion chart — generated from the canonical shoe-size catalog
Foot length (cm)	Foot length (in)	US Women's	UK	EU	Mondopoint	Japan (JP)	China (CN)	Korea (KR)
21.2	8.35	4	2	34	210	21	210	210
21.6	8.50	4.5	2	35	215	21.5	215	215
22.0	8.66	5	2.5	35	220	22	220	220
22.4	8.82	5.5	3	36	225	22.5	225	225
22.9	9.02	6	4	37	230	23	230	230
23.3	9.17	6.5	4	37	235	23.5	235	235
23.7	9.33	7	4.5	38	235	23.5	235	235
24.1	9.49	7.5	5	38	240	24	240	240
24.6	9.69	8	6	39	245	24.5	245	245
25.0	9.84	8.5	6.5	40	250	25	250	250
25.4	10.00	9	6.5	40	255	25.5	255	255
25.8	10.16	9.5	7	41	260	26	260	260
26.2	10.31	10	7.5	42	260	26	260	260
26.7	10.51	10.5	8.5	42	265	26.5	265	265
27.1	10.67	11	8.5	43	270	27	270	270
27.5	10.83	11.5	9	43	275	27.5	275	275
27.9	10.98	12	9.5	44	280	28	280	280

Kids' shoe size conversion chart

Driven by the UK children's ladder, which is the barleycorn line continued below the adult sizes. There is no US column: the US children's ladder restarts at 0 and its junction with the adult ladder is brand-dependent, so it is declared unsupported rather than guessed.

Kids' shoe size conversion chart — generated from the canonical shoe-size catalog
Foot length (cm)	Foot length (in)	UK	EU	Mondopoint	Japan (JP)	China (CN)	Korea (KR)
9.0	3.54	0	—	90	9	90	90
9.4	3.70	0.5	16	95	9.5	95	95
9.8	3.86	1	16	100	10	100	100
10.2	4.02	1.5	17	100	10	100	100
10.7	4.21	2	18	105	10.5	105	105
11.1	4.37	2.5	18	110	11	110	110
11.5	4.53	3	19	115	11.5	115	115
11.9	4.69	3.5	20	120	12	120	120
12.3	4.84	4	20	125	12.5	125	125
12.8	5.04	4.5	21	130	13	130	130
13.2	5.20	5	22	130	13	130	130
13.6	5.35	5.5	22	135	13.5	135	135
14.0	5.51	6	23	140	14	140	140
14.5	5.71	6.5	24	145	14.5	145	145
14.9	5.87	7	24	150	15	150	150
15.3	6.02	7.5	25	155	15.5	155	155
15.7	6.18	8	25	155	15.5	155	155
16.2	6.38	8.5	26	160	16	160	160
16.6	6.54	9	27	165	16.5	165	165
17.0	6.69	9.5	27	170	17	170	170
17.4	6.85	10	28	175	17.5	175	175
17.9	7.05	10.5	29	180	18	180	180
18.3	7.20	11	29	185	18.5	185	185
18.7	7.36	11.5	30	185	18.5	185	185
19.1	7.52	12	30	190	19	190	190
19.5	7.68	12.5	31	195	19.5	195	195
20.0	7.87	13	32	200	20	200	200
20.4	8.03	13.5	32	205	20.5	205	205

US vs EU vs UK shoe sizes

These three systems look similar and are built on completely different ideas, which is why no arithmetic offset converts reliably between them.

The United States ladder measures the foot. The Brannock device, the metal foot-measuring plate in most American shoe shops, anchors men's size 1 at a 7 2/3 inch foot and adds one barleycorn — exactly a third of an inch, about 8.47 mm — for every full size, half that for a half size. Ask it for a length and it hands back a size directly.

The United Kingdom ladder measures the last. It uses the same barleycorn step, which is why UK and US numbers look like a fixed offset, but it counts from a different anchor and it counts the shoe rather than the foot: children's size 0 is a four-inch last, and the adult ladder continues the same line from 8 2/3 inches. Because a last is longer than the foot inside it, a UK number has to be bridged to a foot length before it can be compared with anything metric.

The European ladder also measures the last, in Paris points of two thirds of a centimetre — about 6.67 mm, a smaller step than the barleycorn. The original construction has no half sizes at all, which is the real reason an EU size so often lands between two US half sizes and why converted results here frequently show an adjacent size.

The practical consequence: US↔UK looks like a one-size rule for adult men because the step sizes match, and UK↔EU never looks like a clean rule because the steps differ by nearly two millimetres per size. Both facts fall out of the geometry rather than from any table.

International shoe sizing — Japan, China, Korea and Mondopoint

The Asian systems and Mondopoint are the easy half of this problem, because their numbers are not codes at all — they are measurements.

Mondopoint, defined in ISO 9407, marks the mean foot length in millimetres the shoe is built for, optionally with the foot width. It is the reference system used here and the system used for military and safety footwear precisely because it needs no conversion table.

Japan (JIS S 5037) marks the same measurement in centimetres at half-centimetre steps, so JP 26.5 is a 265 mm foot. Korea (KS M 6681) and China (GB/T 43293-2022, which replaced the older GB/T 3293.1) mark it in millimetres at 5 mm steps, so both write the same foot as 265. That is why Japanese, Korean, Chinese and Mondopoint sizes agree with one another almost perfectly and all four disagree, by varying amounts, with US, UK and EU.

Two consequences worth knowing before you order from an Asian retailer: a metric marking tells you the foot the shoe was designed for, so it is the most directly comparable number to your own measurement; and Chinese sellers frequently mark shoes with EU or US numbers as well, which are their own conversion of the metric size and not necessarily the same as the one shown here.

Men vs women shoe sizing

Whether men's and women's sizes differ depends entirely on which system you are in. In the European, Mondopoint, Japanese, Korean and Chinese ladders the number describes the foot, so it is the same number for everyone; only the last the shoe is built on changes. In the United States they are two different scales, so the same foot receives two different numbers — and how different is genuinely disputed.

The Brannock measuring device offsets its women's scale by one size from its men's scale. Most United States retail size charts use one and a half. Both are in wide use, and neither is wrong so much as they are answering slightly different questions: one is a measurement instrument, the other is a fitting convention. This converter refuses to pick. It takes your size to a foot length, finds every size in the target scale whose interval covers that length, reports the closest one and shows the whole range, and marks the result variable by source. That is why a men's 9 comes back as a women's 10 with 9.5 to 11 in range rather than as a bare number.

Shoe width guide

Width is a different dimension from length, and changing your length size is the wrong way to fix it. Going up a size to gain room across the ball makes the shoe too long, which lets the heel slip and drives the toes into the front on every step. If a shoe that matches your foot length feels tight across the ball, the fix is a wider fitting in that same length.

Width nomenclature is manufacturer-specific and does not form a single ladder. American brands typically letter widths from narrow to wide (2A, B, D, 2E, 4E), with the same letter meaning a different measurement for men's and women's lasts. British and European brands often use G, F, H or a numeric fitting instead, and many brands publish no width at all and simply build one standard fitting.

No numeric width conversion is offered on this page, and that is deliberate. A width letter only has a measurement attached to it inside one manufacturer's system, and no verifiable cross-brand width dataset was available that met the sourcing bar the rest of this catalog is held to. Publishing a width conversion table would mean inventing one. Instead: measure the ball of your foot at its widest point, compare it against the specific brand's own width chart for the length you need, and treat a width letter as a brand-internal code rather than a portable size.

Why shoe-size conversions differ

If you compare five shoe-size charts you will find five slightly different answers for the same input. The disagreement is real and it has four identifiable causes.

Foot systems versus last systems. Mondopoint, Japanese, Korean, Chinese and US numbers describe a foot; UK and EU numbers describe a last. Any chart crossing that line has to assume how much longer the last is than the foot, and different publishers assume different amounts. This page discloses the interval it uses — 12–18 mm for adults, 9–15 mm for children — instead of hiding a constant.
Different step sizes. A barleycorn is about 8.47 mm and a Paris point about 6.67 mm. Two ladders with different rungs cannot align everywhere, so any single-number mapping is right at some sizes and half a size off at others.
Measurement versus recommendation. A measuring device answers "what size is built for this foot?"; a retail chart answers "what size should this customer order?", which quietly includes fit preference. Those are different questions and they produce answers up to half a size apart, particularly between the US ladder and the metric ones.
Brands build to their own lasts. A standard defines what a marked number should mean; it does not compel anyone to build to it. Two shoes marked EU 42 from different makers routinely differ by half a size of usable length.

Technical conversion vs retail recommendation

This page gives you the technical conversion: the size whose published foot-length reference is closest to yours, with the range and the rule that produced it. A retailer's chart gives you a recommendation: the size their customers are happiest ordering in that brand, in that model, with that last. The two are not the same document and should not be expected to agree to the size.

Use the technical conversion to understand what a number means and to compare across systems — it is stable, auditable and does not change with fashion. Use the retail chart to decide what to actually put in the basket for one specific shoe. Where they disagree, the retail chart wins for that purchase and the technical conversion still tells you why they disagree.

Common shoe-size conversion mistakes

Treating EU sizing as universal across brands. An EU number is a Paris-point last count, not a guarantee. Two brands marking EU 42 can differ by half a size of usable length, and neither is mislabelled.
Hard-coding a men-to-women offset. "Women's = men's + 1.5" is a retail convention, not a definition; the measuring device says 1.0. Convert through foot length and read the range instead.
Confusing foot length with shoe length. Measuring the insole of a shoe you own gives the last length. It is longer than your foot by the fitting allowance and will size you up by a size or more.
Measuring only one foot. Feet routinely differ by several millimetres — more than half a size — so a single measurement is a coin flip.
Choosing the smaller foot. Sizing to the smaller foot guarantees one shoe is too short. Size to the longer one and adjust the other with lacing or an insole.
Ignoring half sizes. A half size is about 4.2 mm. Rounding it away is a real fit change, and it is exactly the amount that separates comfortable from bruised on a long day.
Assuming adjacent international systems are mathematically equivalent. UK and US share a step but not an anchor; EU and UK share neither. A fixed number added to a size is never a conversion.
Treating a sizing recommendation as an exact conversion. Only the millimetre, centimetre and inch conversions on this page are exact. Everything with a size number attached is a guideline, and it is labelled as one.

How CalcDomain builds and verifies these conversions

Every conversion passes through one canonical bridge — integer foot length in millimetres. There is no size-to-size arithmetic anywhere in the engine.
Each supported system is generated from a stated rule, not transcribed from a chart: Mondopoint and the Japanese, Korean and Chinese ladders are foot length by definition; the US ladder follows the Brannock scale ((size + 22) ÷ 3 inches for men); the UK ladder is barleycorns of 1/3 inch of last; the EU ladder is Paris points of 2/3 cm of last.
Last-length ladders are bridged to foot length by an explicitly disclosed allowance interval — 12–18 mm for adults (nominal 15 mm), 9–15 mm for children (nominal 12 mm). The nominal values are calibrated so the Paris-point and barleycorn ladders line up with the foot-length-defined systems; they are not measured from shoes, and saying so is part of the method.
Every record is an interval, not a point. The target size is the record whose nominal foot length is closest; every target record whose interval overlaps yours is reported as the observed range.
Agreement is reported as strong, moderate or variable — the weaker of the two systems' grades. No confidence percentage is invented, because there is nothing to compute one from.
Where two target sizes are equally close, the larger one is chosen, matching the standing advice to take the bigger size when you are between sizes.
A system that cannot be supported from a verifiable rule is declared unsupported and returns an explanation instead of a number. Mexico, India and the US children's ladder are currently in that state.
The server-rendered result and the in-browser result come from the same engine source, so they cannot disagree, and every chart on this page is generated from the same catalog as the calculator.
The receipt's consistency check is honestly labelled: it re-enters the same catalog, so it is a granularity self-check, not independent verification.
Automated invariants run on every build: monotonicity of foot length within each ladder, interval integrity (min ≤ nominal ≤ max), unique keys, 100% provenance with no orphan source ids, population separation, boundary behaviour, round-trip tolerance derived from each system's own granularity, and server/browser parity.

Author: Ugo Candido · Last reviewed: August 9, 2026 · Engine: shoe-size-engine v1.0.0 · Catalog: shoe-size-catalog v1.0.0 · Every conversion runs in your browser; nothing you enter is sent to a server. See the public changelog.

External review status: No independent third-party review of this dataset has taken place, and none is claimed. The catalog is generated from published construction rules rather than transcribed from charts, and quality is enforced by automated invariants that run on every build: monotonic foot length within every system and population, min-nominal-max interval integrity, unique (system, population, size) keys, 100% source-id coverage with no orphan source references, semantic separation of US men's and women's ladders, boundary behaviour at the smallest and largest supported sizes and outside them, round-trip tolerance derived from each system's own marking granularity, server/browser parity of the structured result, and golden vectors on the foot-length bridge.

Assumptions this calculator makes

A shoe size is a marking convention, not a unit: two systems relate to each other only through the foot the shoe is built for, so every conversion here passes through foot length in millimetres.
Foot length means the longer foot, measured heel to longest toe while standing with weight on the foot.
Foot length is not shoe length: a last is longer than the foot inside it, which is why last-length ladders (UK, EU) need a disclosed allowance and foot-length ladders (Mondopoint, JP, KR, CN, US) do not.
The last allowance is an interval, not a constant — adults 12 to 18 mm, children 9 to 15 mm — and its nominal value is calibrated so the Paris-point and barleycorn ladders line up with the foot-length-defined systems, not measured from shoes.
Where two target sizes sit equally far from the reference foot length, the larger one is reported, matching the standing advice to take the bigger size when you are between sizes.

Limitations

Mexican and Indian sizing are not supported: no normative rule tying their printed numbers to a foot length could be verified, and plausible numbers are not invented to fill the gap.
United States children's and youth sizes are not supported: the ladder restarts at 0 and its junction with the adult ladder is brand-dependent, so no single verifiable foot-length rule exists.
Width is covered editorially only. Width nomenclature (B, D, 2E, EE, G) is manufacturer-specific and no verifiable width-to-measurement dataset was available, so no numeric width conversion is offered.
The United States ladder is anchored on the Brannock measuring scale. Many retail charts sit up to half a size away from it against metric systems, which is a real divergence between technical measurement and retail recommendation rather than an error in either.
Half sizes exist in the US and UK ladders but not in the original EU Paris-point construction, so an EU size regularly sits between two US half sizes and the observed range shows both.
Nothing here predicts fit. Toe shape, instep volume, last shape, material and the model itself change how a given marked size feels.

Sources and licensing

Every production record in the catalog cites one of these source ids, and every one of them is a rule rather than a table. No conversion chart is reproduced from a competitor calculator, a retailer, an encyclopaedia or a paywalled standards document — the standards below are cited for their methodology and for the definitional statement each makes about its own system.

Tier 1ISO (International Organization for Standardization)
ISO 19407:2023 — Footwear — Sizing — Conversion of sizing systems 2023 (first edition, June 2023; replaces ISO/TS 19407:2015) · reference-only · reviewed August 9, 2026 Methodological reference for this calculator. Establishes that shoe-size conversion between Mondopoint, European, United Kingdom, China, Japan, Republic of Korea and United States systems is performed through FOOT LENGTH, "this being the logical starting point for any shoe size marking system". Prepared by ISO/TC 137. The three numeric conversion tables in this standard (adults technical, adults simplified marking, children) are copyrighted and sold behind a paywall. They are NOT reproduced in this repository. Only the documented approach — convert via foot length, never by arithmetic offset between size numbers — is adopted.
Tier 1ISO (International Organization for Standardization)
ISO 9407:2019 — Footwear — Sizing — Mondopoint system of sizing and marking 2019 (second edition) · reference-only · reviewed August 9, 2026 Defines the Mondopoint system: a shoe is marked with the MEAN FOOT LENGTH in millimetres that it is designed to fit (optionally with foot width). This definitional rule — Mondopoint size number = foot length in mm — is what the catalog generates from. Mondopoint needs no conversion table: the size IS the measurement. The catalog generates the Mondopoint ladder arithmetically at the 5 mm marking interval; nothing is copied.
Tier 1Japanese Industrial Standards Committee / Japanese Standards Association
JIS S 5037 — Sizing systems and marking for footwear Current edition as listed in the JIS catalogue · reference-only · reviewed August 9, 2026 Establishes that Japanese footwear sizes designate FOOT LENGTH IN CENTIMETRES: a shoe marked 26 is built for a 26 cm foot. Marking interval 0.5 cm. Confirmed independently by ISO 19407:2023, which lists Japan among the foot-length-based systems it converts. Only the definitional rule is used. The Japanese ladder is generated as foot length in centimetres at 0.5 cm steps; no JIS table is reproduced.
Tier 1Korean Agency for Technology and Standards (KATS)
KS M 6681 — Sizing system and marking for footwear Current edition as listed in the KS catalogue · reference-only · reviewed August 9, 2026 Establishes that Korean footwear sizes designate FOOT LENGTH IN MILLIMETRES at a 5 mm marking interval — a shoe marked 260 is built for a 260 mm foot. Confirmed independently by ISO 19407:2023, which lists the Republic of Korea among the foot-length-based systems it converts. Only the definitional rule is used; the ladder is generated arithmetically. No KS table is reproduced.
Tier 1Standardization Administration of China (SAC) / SAMR
GB/T 43293-2022 — Shoe sizes (replaces GB/T 3293.1-1998) 2022 (issued 2022-10-12) · reference-only · reviewed August 9, 2026 Establishes that Chinese footwear sizes designate FOOT LENGTH IN MILLIMETRES — the 1998 revision moved the system from centimetres to millimetres, so a foot length of 230 mm corresponds to size 230. Confirmed independently by ISO 19407:2023, which lists China among the foot-length-based systems it converts. Only the definitional rule is used; the ladder is generated arithmetically at the 5 mm marking interval. No GB/T table is reproduced.
Tier 2The Brannock Device Company (Liverpool, New York)
The Brannock Device® foot-measuring scale — the US retail foot-measuring standard Scale unchanged since the 1927 design; reviewed against the current product documentation · reference-only · reviewed August 9, 2026 Defines the United States retail sizing scale as a FOOT-LENGTH scale: men’s size 1 corresponds to a 7 2/3 inch foot, every full size adds 1/3 inch (one barleycorn) and every half size 1/6 inch; the women’s scale on the same device is offset by one size from the men’s scale for the same foot length. The scale RULE (anchor + increment + inter-scale offset) is used to generate the US ladders; the printed size chart is not reproduced. Important caveat carried into every cross-gender result: United States retail practice widely uses a 1.5-size men-to-women offset while the measuring device itself uses 1.0, so cross-gender conversions are reported as variable by source rather than as a single number.
Tier 3Public-domain historical construction — English barleycorn shoe-size progression
Barleycorn last-length progression (1 barleycorn = 1/3 inch) Construction rule; CalcDomain derivation published on-page and in docs/shoe-size-converter.md · public-domain-rule · reviewed August 9, 2026 United Kingdom sizes are LAST LENGTH expressed in barleycorns of exactly 1/3 inch. Children’s size 0 is a 4 inch last and each size adds 1/3 inch, so children’s size C has a last of (12 + C)/3 inches; the adult ladder continues the same line, so adult size A has a last of (25 + A)/3 inches (adult 1 = 8 2/3 inches, immediately above children’s 13.5). This is a geometric construction rule, not an authored dataset: no third-party table is reproduced. Because it yields LAST length rather than foot length, every UK record is bridged to foot length through the disclosed allowance interval (see calcdomain-last-allowance) and is therefore reported as source-dependent, never exact.
Tier 3Public-domain historical construction — Continental European Paris point
Paris point last-length progression (1 Paris point = 2/3 centimetre) Construction rule; CalcDomain derivation published on-page and in docs/shoe-size-converter.md · public-domain-rule · reviewed August 9, 2026 Continental European sizes are LAST LENGTH expressed in Paris points of exactly 2/3 cm (6.666… mm), with no half sizes in the original construction: EU size E has a last of E × 20/3 millimetres. A geometric construction rule, not an authored dataset. Like the UK ladder it yields LAST length, so every EU record is bridged to foot length through the disclosed allowance interval and reported as source-dependent, never exact.
Tier 3CalcDomain (own work, fully disclosed)
Last-length to foot-length allowance interval used to bridge the UK and EU ladders v1.0.0 (2026-08-09) · own-work · reviewed August 9, 2026 A shoe last is longer than the foot it fits. The UK barleycorn and EU Paris-point ladders measure the LAST; Mondopoint, Japan, Korea and China measure the FOOT. Bridging them needs an allowance. CalcDomain uses an interval, not a point value: adults 12–18 mm (nominal 15 mm), children 9–15 mm (nominal 12 mm). The nominal values are CALIBRATED, not measured: they are the allowances at which the Paris-point and barleycorn last ladders line up with the foot-length-defined systems (Mondopoint, JP, KR, CN) across the supported range. The interval width is the honest uncertainty, and it is what makes UK and EU results carry an observed range and a source-dependent status instead of a bare number. Real allowances vary by last, toe shape and manufacturer, which is exactly why no single value is presented as fact.

Systems this converter does not support

A conversion that is explicitly unavailable is more useful than a conversion that is quietly wrong. These systems are declared unsupported rather than filled in with plausible numbers, and the converter returns an explanation instead of a size when you select them.

Mexico (MX) — Mexican footwear is marked with several incompatible conventions — a centimetre foot-length number, a "Mexican point" last number and imported US numbers all circulate — and no single normative rule could be verified to the standard this catalog requires. What would unlock it: A citable NMX/NOM footwear-sizing standard, or a Mexican manufacturer publishing its marking rule, stating what the printed number measures.
India (IN) — Indian footwear is commonly described as following the UK ladder, but the offset actually applied varies by manufacturer and no normative Indian rule tying the printed number to a foot length could be verified. What would unlock it: A citable BIS (Bureau of Indian Standards) footwear-sizing standard stating the marking rule, or an Indian manufacturer publishing it.
US Kids' / Youth — The United States children's ladder restarts at 0 and its junction with the adult ladder is brand-dependent — some brands map youth 7 to men's 7, others to men's 7.5 — so no single verifiable foot-length rule exists for it. What would unlock it: A published Brannock youth-scale anchor, or an industry standard fixing where the youth ladder meets the adult ladder.

Frequently asked questions

How do shoe size conversions work?

Through foot length, not arithmetic. Each sizing system states — or can be derived to state — the foot length its numbers designate. To convert, you look up the foot length behind your size, then find the size in the target system built for that same foot length. Adding or subtracting a fixed number from a size is the wrong model, because the systems have different step sizes and different starting points.

How do I convert US shoe size to EU?

Take the foot length your US size designates and find the EU size built for it. On the Brannock scale a US men's size is (size + 22) ÷ 3 inches of foot; an EU size is that number of Paris points of last, two thirds of a centimetre each, less the fitting allowance. US Men's 9 lands on EU 42 with EU 41 in range, US Men's 10 on EU 43, and US Men's 11 on EU 44 — but check the observed range, because EU sizes have no half steps.

How do I convert UK shoe size to US?

UK and US ladders share the same barleycorn step of one third of an inch, which is why they look like a simple offset, but they are anchored differently and the UK number measures the last while the US number measures the foot. Converting through foot length, UK 6 lands on US Men's 7 and UK 9 on US Men's 10. The one-size rule of thumb works for most adult men's sizes; it is not a definition, and it does not hold for women's or children's ladders.

What shoe size is my foot length in centimetres?

In Japan the number is your foot length in centimetres, so a 26 cm foot is JP 26; Korea and China use the same measurement in millimetres, so 260. In Mondopoint it is also 260. For US, UK and EU the answer is a lookup rather than a restatement: use Measure my foot, enter 26 cm, and the page returns the closest size in every supported system plus the range.

Are men's and women's shoe sizes the same?

No, and the difference is not the same everywhere. In the United States men's and women's numbers are different scales, so the same foot gets different numbers. In the European, Mondopoint, Japanese, Korean and Chinese systems the number is the same for everyone, because it describes the foot rather than the wearer — only the shoe's last differs.

How do men's and women's US shoe sizes compare?

This is the single most disputed relationship in shoe sizing. The Brannock measuring device offsets its women's scale by 1.0 size from the men's scale; most United States retail size charts use 1.5. Rather than pick one, this converter goes through foot length and reports the range that covers both — a men's 9 comes back as women's 10 with 9.5 to 11 in range — and marks the result variable by source.

Are EU shoe sizes the same for men and women?

The number is. An EU 40 designates the same last length whoever wears it, because the European ladder counts Paris points of last rather than addressing a gender. Men's and women's shoes marked EU 40 are still built on different lasts — different width, instep and toe shape — so the fit differs even though the number does not.

Are shoe sizes standardized between brands?

No. A standard fixes what a marked number should mean; it does not force a manufacturer to build to it, and most brands work from their own lasts. That is why two shoes marked EU 42 from different brands can differ by half a size in usable length. Treat any conversion, including this one, as the starting point and check the manufacturer's own chart for the model you are buying.

What is Mondopoint?

Mondopoint is the sizing system defined in ISO 9407, in which the marked size is the mean foot length in millimetres that the shoe is built to fit, optionally with the foot width. It needs no conversion table because the size is the measurement, which is why it is used as the reference system here and in military and safety footwear.

Is Japanese shoe sizing based on centimetres?

Yes. Japanese sizes under JIS S 5037 designate foot length in centimetres at half-centimetre steps, so JP 26.5 is built for a 265 mm foot. That makes Japanese sizing Mondopoint expressed in centimetres, and it is why Japanese, Korean, Chinese and Mondopoint numbers agree with each other far more closely than any of them agrees with US, UK or EU.

Why do different shoe-size charts disagree?

Because they are bridging different kinds of number. Mondopoint, Japanese, Korean and Chinese sizes measure the foot; UK and EU sizes measure the last, which is longer than the foot by an allowance that varies with toe shape and manufacturer. Any chart that maps between the two families has to assume an allowance, and different publishers assume different ones. This page discloses the interval it uses instead of hiding a constant.

Should I measure both feet?

Yes, and size to the longer one. Most people have feet that differ by a few millimetres, which is enough to cross a half-size boundary. Measure standing, with weight on the foot, at the end of the day when feet are at their largest, and record the length in millimetres — a whole size is only about 8.5 mm, so a 5 mm reading error is more than half a size.

Does shoe width change shoe size?

It should not, but in practice people compensate. Width is a separate dimension with its own manufacturer-specific letters (B, D, 2E, EE, G), and going up a length size to gain width makes the shoe too long, which causes heel slip and toe bruising. If a size that matches your foot length feels tight across the ball, look for a wider fitting in that same length rather than a longer shoe.

What should I do if I am between sizes?

Take the larger size and manage the fit with lacing, a thicker sock or an insole. Length that is slightly generous is adjustable; length that is short is not. This converter follows the same rule: when two target sizes sit equally far from your foot-length reference, it reports the larger one, and it always shows the adjacent size when one genuinely overlaps.