How do you convert a women's clothing size between France, the UK and the US?

In short:

1. To convert a French size, subtract 26 for the UK size (FR 38 = UK 10) and 30 for the US size (FR 38 = US 6); add 4 for the Italian size (FR 38 = IT 42).
2. A size only means something through body measurements: a French 40 covers 86 to 94 cm of bust girth across the two French size guides consulted on 20 October 2026.
3. The European standard EN 13402 sets out a way to label clothes in centimeters, but applying it is voluntary.
4. Letter sizes from XS to XXL follow no shared scale: depending on the brand, an M runs from a French 38 to a 44.

This women’s size conversion chart rests on fixed gaps: 26 points between a French size and a UK size, 30 points with a US size. A French 38 becomes a UK 10 and a US 6. Those rules are a starting point. The real judge is the tape measure, because two brands from the same country do not always dress the same body with the same number.

Women’s size conversion chart

The chart below gives the most common equivalents for tops, dresses, jackets and pants sold with a numbered size. German and Dutch sizes have their own column, since they are often what hides behind an “EU” label.

Two caveats before you use it. The equivalents vary from one source to another, above all in the US column: some brands put a French 38 on a US 8 rather than a US 6. And the letter column only shows a trend, because each brand splits its XS to XXL range its own way.

Reference body measurements in centimeters: bust, waist, hips

A clothing size stands for a range of body measurements, not a measurement of the garment. That is the principle of the European standard EN 13402-3 (September 2017 edition), which describes a sizing system built on body dimensions. For women, three measurements matter: bust girth, waist girth and hip girth.

The next table gives general benchmarks. It combines the ranges published by two size guides from French retailers, consulted on 20 October 2026: each cell runs from the lowest to the highest value of the two guides.

The gap is plain to see. For the same French 40, one guide gives 86 to 89 cm of bust girth and the other 90 to 94 cm: a 4 cm shift, which is a whole size. These figures are benchmarks. Every brand publishes its own size guide, and that guide is the one that counts for the piece you are buying.

How to take your measurements

A soft tape measure is all you need, ideally with someone else to keep it level across your back. Measure in underwear, standing with your feet together, without pulling the tape tight.

1. Bust: horizontally, around the fullest part of the chest, under the arms.
2. Waist: at the natural waistline, usually a few centimeters above the navel.
3. Hips: around the fullest part of the seat, tape parallel to the floor.
4. Inseam, for pants: from the crotch to the floor, barefoot.

Write each measurement down in centimeters. If your measurements fall into two different sizes, go by the part of the body the garment has to follow: the bust for a shirt, the hips for a straight skirt.

How to convert a UK or US size into a French size

Three calculations cover most cases. They apply to women’s ready-to-wear with numbered sizes, not to lingerie or shoes.

• UK size to French size: add 26. A UK 10 gives a French 38, a UK 14 a French 42.
• US size to French size: add 30. A US 6 gives a French 38, a US 10 a French 42.
• Italian size to French size: subtract 4. An IT 44 gives a French 40.
• German size to French size: add 2. A German 38 gives a French 40.

Between UK and US sizes the gap is 4: a UK 12 is a US 8. That is the steadiest of the three conversions. The shakiest is the US size, for a documented reason: American size tables have drifted down over the years. The ASTM D5585 standard, the body measurement table behind US “misses” sizes, covered sizes 2 to 20 in its 1995 edition. Its 2011 and 2021 editions cover sizes 00 to 20. The result: one American brand may dress you in a 4 where another dresses you in an 8.

The “EU” label: French or German?

The “EU” label is confusing. There is no single European numbering: France, Belgium and Spain generally use the same numbers, Germany and the Netherlands a numbering 2 lower, Italy a numbering 4 higher. A brand that prints “EU 36” may mean a French 36 or a German 36, which is a French 38. The brand’s size guide settles it: look for the line that ties the “EU” size to a bust measurement.

Letter sizes, from XS to XXL

Letters are the vaguest convention. No standard defines what an S or an XL covers. Depending on the guide, an M matches a French 38, 40, 42 or 44: the same letter can span four French sizes from one brand to the next. With knitwear, where letters dominate, the gap is easier to absorb, since a knit stretches. If you are comparing wool and cashmere sweater brands for women, look at the bust range for each letter rather than the letter itself.

What the standards say: EN 13402, ISO 8559 and ASTM D5585

The equivalents in the chart do not come from any official text. They are trade conventions. The standards took another path: replacing numbers with centimeters.

• EN 13402 is the European standard for the size designation of clothes. Its part 1 defines body measurements, how to take them and the pictogram to print on the label. Its part 3, in the September 2017 edition, describes size labeling based on body measurements and the intervals between sizes.
• ISO 8559-1 (2017) plays a similar role at international level. The text, presented on the ISO website, describes the anthropometric measurements used for clothing and how to take them, with an annex on the use of the size pictogram.
• ASTM D5585 is the reference body measurement table for American women’s sizes, from 00 to 20 in its 2021 version.

The EN 13402 pictogram shows a body outline and, next to it, the body measurements the garment is made for: for instance 88 cm of bust and 96 cm of hips. It is the clearest tool for buying abroad. But like any European standard, applying it is voluntary, and most labels still show a national number or a letter.

Why your size changes from one brand to another

Even with an accurate chart, you can wear a 38 in one brand and a 42 in another. Several causes add up.

Each brand has its own measurement base. The base size, the one the pattern is drafted on, differs from brand to brand, and so does the step between two sizes: the two guides consulted move up by 4 cm of bust girth in the middle of the range, then by 5 or 6 cm in larger sizes, but they do not start from the same point.

The cut matters as much as the size. A straight cut and a slim cut with the same number do not give the same ease, meaning the room between body and fabric. On wide-leg vs palazzo trousers, the leg width forgives a lot: only the waist and the inseam really decide the size.

The fabric changes the drape. A fabric with elastane, a knit or a tight weave do not react the same way over the same measurement. A fine, soft fiber such as cashmere follows the body more closely than a springier wool; the cashmere vs merino comparison covers these differences in hand and hold.

The brand’s home country. A British or American brand selling in France often shows its own in-house conversion. It can be one step off from the chart above.

Choosing your size when you order from abroad

A five-step method cuts down on returns.

1. Measure yourself once (bust, waist, hips, inseam) and keep the numbers on your phone.
2. Open the brand’s own size guide, not a generic chart: it is the one that ties each size to centimeters.
3. Identify the convention: UK size, US size, French or German numbering behind the “EU” label.
4. Pick the size from the measurement that matters for the piece: the bust for a top, the hips for a skirt, the waist for pants.
5. Between two sizes, take the larger one for a fitted piece without elastane, the smaller one for a knit that stretches.

Jeans work differently. They are often sized in inches, with a W for the waist and an L for the leg length: that system does not convert with the rules in this article.