US Women’s Size to UK

A US women’s size converts to UK by adding four: a US 8 is a UK 12. That is the whole rule, and it holds right along the range — a US 4 is a UK 8, a US 12 is a UK 16, a US 16 is a UK 20. The number itself is not a measurement in either country: unlike men’s tailoring, where a 40 is literally a 40-inch chest, a women’s …

12

8 US (numeric) = 12 UK (numeric)  ·  bust ≈ 91 cm (35.8 in)

8 US (numeric) IN EVERY SYSTEM

LETTER SIZE

REGIONAL SIZES

BUST MEASUREMENT

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HOW TO USE

  1. 1

    This page is preset to US → UK. Type your US size (the default is 8) and read the UK size.

  2. 2

    The rule is simply UK = US + 4, so a US 8 is a UK 12 and a US 14 is a UK 18.

  3. 3

    Check the bust shown beneath (a US 8 ≈ 91 cm / 35.8 in), or tap ⇄ to reverse to UK → US.

  4. 4

    Switch either side to EU, Italy, France, Japan, letters or the bust in cm in the dropdowns, then Share or Embed your conversion.

QUICK REFERENCE

US 8

EU 38

M

US 8

UK 12

US 8

US 6

IT 42

EU 38

UK 12

S

Bust 87 cm

JP 11

US 8

L

EU 42

US 4

FR 36

Bust 91 cm

M

ABOUT WOMEN’S CLOTHING SIZES

Women’s sizing works differently from men’s, and it catches people out. A men’s 40 is literally a 40‑inch chest, so the maths is exact. A women’s US 8 is not “8” of anything — it is just the eighth step on an arbitrary ladder, and every country numbers that same ladder differently. Line them up against the bust and the pattern appears: the UK adds four to the US number, Germany and the wider EU add thirty, France adds thirty‑two, and Italy and Russia add thirty‑six — so one garment that fits a 91‑cm (36‑inch) bust is a US 8, a UK 12, a EU 38, a French 40, an Italian 44 and a Japanese 11, all at once. Letters sit on top of that ladder, each one covering two US sizes: S is a US 4–6, M a US 8–10, L a US 12–14. Korea’s 44–99 run works the same way, and China codes the garment as height/bust — 165/88A means a 165‑cm frame with an 88‑cm bust. Because the steps are bands rather than points, converting always snaps to the nearest standard size, and no chart can beat the brand’s own: women’s sizing carries decades of vanity sizing, so the same body can be a 6 in one shop and a 10 in the next. Measure your bust at its fullest point with the tape level and snug, treat the number as a starting point, and size up if you are between sizes or prefer room.

FREQUENTLY ASKED QUESTIONS

Add four. A US women’s number plus four is the UK size, so a US 8 is a UK 12, a US 4 is a UK 8 and a US 14 is a UK 18. Both describe the same garment; only the label changes.

  • UK = US + 4.
  • US 8 → UK 12.
  • US 14 → UK 18.
  • Same garment, different label.

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Last updated: · 14 women’s clothing systems · Bust-based conversions (UK = US + 4; EU/DE = US + 30; FR = US + 32; IT/RU = US + 36; JP = US + 3); sizes snap to the nearest standard size and letter sizes are approximate · Verified by the EagleCalculator team · Eagle-eyed accuracy for every calculation.