US vs UK vs EU vs AU Dress Sizes: The Conversion Chart (and the Logic Behind It)

You found the perfect dress. It’s from a UK site. You wear a US 8. Do you buy a 8, a 12, or throw your laptop out the window? Let’s fix this before you need a new laptop.

The short version

Roughly speaking, here’s how the major systems line up for women’s dresses:

US	UK	EU	AU	International
0	4	32	4	XXS
2	6	34	6	XS
4	8	36	8	XS
6	10	38	10	S
8	12	40	12	S
10	14	42	14	M
12	16	44	16	M
14	18	46	18	L
16	20	48	20	L
18	22	50	22	XL
20	24	52	24	XL

Want it calculated automatically from your actual measurements instead of squinting at a table? Our dress size calculator does this instantly and tends to be more accurate than a static chart, because it accounts for your specific bust, waist, and hip numbers rather than one label.

Why the numbers are so different in the first place

Here’s the part nobody explains: these aren’t arbitrary offsets someone made up to confuse you. Each country built its sizing system independently, around different historical average body measurements and different comfort with “small” numbers.

The UK and Australia both traditionally add about 4 to the US number for the same body. The EU system skips small numbers entirely and starts higher, jumping straight to the 30s and 40s, which is why an EU 40 sounds enormous but is a completely normal, very average size. International sizing (XS through XXL) exists because letters feel less personal than numbers, which, fair enough.

The offsets are approximate, not gospel

We wish we could tell you “just add 4 and you’re done,” but sizing charts vary by brand more than they vary by country. A UK 12 at one shop might be a UK 10 at another. This is the same vanity sizing phenomenon we cover in our guide to why dress sizes differ between brands, just with a passport stamp.

The safest approach when shopping internationally:

1. Measure yourself in inches or centimeters (your body doesn’t care what country it’s in).
2. Use our calculator to get your closest match in every system at once.
3. If the retailer publishes their own size chart in centimeters or inches (many international sites do), trust that over the generic label every time.

A few sizing curveballs to watch for

• Japanese and Korean sizes run noticeably smaller than Western sizes for the same measurements. A US 8 might be a Japanese 11 or 13, not anywhere close to an 8.
• Vintage and secondhand dresses were sized before most modern vanity sizing crept in, so a “vintage size 12” often fits like a modern size 6 to 8. Always measure a vintage piece flat rather than trusting the tag.
• Bridal and formalwear tends to run a full size smaller than everyday ready-to-wear, which is its own special kind of chaos we go into more in our complete dress size guide.

The one thing to actually remember

Numbers lie, tape measures don’t. Whatever system a dress uses, it was designed around the same three measurements: bust, waist, hip. Get yours, run them through the calculator, and you’ll never have to do mental gymnastics with a size chart again.