Bra Cup Size International Conversion and Equivalencies
Bra Cup Size International Conversion Chart
The chart below covers US cup sizes from AAA to O, showing equivalents across UK, Europe, Australia, Japan, and China, based on bust-underbust measurement differences in inches and centimeters.
|
Bust-Underbust Difference
|
US
|
UK
|
Europe
|
Australia
|
Japan
|
China
|
|---|---|---|---|---|---|---|
|
<0.5 in (<1.27 cm)
|
AAA
|
—
|
—
|
—
|
—
|
—
|
|
0.5–1 in (1.27–2.54 cm)
|
AA
|
AA
|
AA
|
AA
|
AA
|
AA
|
|
1–2 in (2.54–5.08 cm)
|
A
|
A
|
A
|
A
|
A
|
A
|
|
2–3 in (5.08–7.62 cm)
|
B
|
B
|
B
|
B
|
B
|
B
|
|
3–4 in (7.62–10.16 cm)
|
C
|
C
|
C
|
C
|
C
|
C
|
|
4–5 in (10.16–12.7 cm)
|
D
|
D
|
D
|
D
|
D
|
D
|
|
5–6 in (12.7–15.24 cm)
|
DD/E
|
DD
|
E
|
DD
|
E
|
E
|
|
6–7 in (15.24–17.78 cm)
|
DDD/F
|
E
|
F
|
E
|
F
|
F
|
|
7–8 in (17.78–20.32 cm)
|
G
|
F
|
G
|
F
|
G
|
G
|
|
8–9 in (20.32–22.86 cm)
|
H
|
FF
|
H
|
FF
|
H
|
H
|
|
9–10 in (22.86–25.4 cm)
|
I
|
G
|
I
|
G
|
I
|
I
|
|
10–11 in (25.4–27.94 cm)
|
J
|
GG
|
J
|
GG
|
J
|
J
|
|
11–12 in (27.94–30.48 cm)
|
K
|
H
|
K
|
H
|
K
|
K
|
|
12–13 in (30.48–33.02 cm)
|
L
|
HH
|
L
|
HH
|
L
|
L
|
|
13–14 in (33.02–35.56 cm)
|
M
|
J
|
M
|
J
|
M
|
M
|
|
14–15 in (35.56–38.1 cm)
|
N
|
JJ
|
N
|
JJ
|
N
|
N
|
|
15–16 in (38.1–40.64 cm)
|
O
|
K
|
O
|
K
|
O
|
O
|
Overview of Cup Size Systems
-
Cup Size Basis: Cup sizes are determined by the difference between the bust (fullest point) and underbust (snug) measurements. Generally, each 1-inch (2.54 cm) difference corresponds to one cup size (e.g., 1 inch = A, 2 inches = B).
-
Regional Variations:
-
US: Uses AAA, AA, A, B, C, D, DD, DDD/F, G, H, I, J, K, L, M, N, O, with some brands varying (e.g., DDD vs. F).
-
UK: Uses AA, A, B, C, D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, with double letters after D.
-
Europe: Uses AA, A, B, C, D, E, F, G, H, I, J, K, L, M, N, with band sizes in centimeters.
-
Australia: Aligns closely with UK sizing (AA, A, B, C, D, DD, E, F, FF, etc.).
-
Japan: Uses AA, A, B, C, D, E, F, G, H, I, J, K, L, M, N, with band sizes in centimeters.
-
China: Similar to Japan, uses AA, A, B, C, D, E, F, etc., with local band size conventions.
-
Notes on the Chart
-
AAA Cup: The AAA cup (US) is for differences less than 0.5 inches, rare in most systems outside the US. Other regions typically start at AA or A.
-
Measurement Precision: Differences are approximate; brands may round up or down (e.g., a 5.5-inch difference might be DD or DDD depending on the brand).
-
US Variations: US sizing uses DD, DDD (sometimes F), and single letters beyond (G, H, I, etc.). Some brands label DDD as F or E.
-
UK Double Letters: UK sizing introduces double letters (DD, FF, GG, HH, JJ) after D, which shifts equivalencies (e.g., UK E = US DDD/F).
-
Europe and Japan: Use single letters and align closely, with band sizes in centimeters (e.g., 70, 75, 80). Japan extends to larger cups (N, O) in some brands.
-
Australia: Mirrors UK sizing but may vary slightly by brand.
-
China: Aligns with Japan/Europe for cup sizes, but band sizes may follow local conventions.
-
Fit Caveats: Cup size equivalencies assume consistent band sizes, but fit varies by bra style, brand, and body shape.
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send an email to billysbras@gmail.com