Cup Size Chart
Each cell shows the full size label and the bust range (in cm or inches) it is designed to fit.
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | DD |
| 14.0–16.5 cm | DDD |
| 16.5–19.1 cm | G |
| 19.1–21.6 cm | H |
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | DD |
| 14.0–16.5 cm | E |
| 16.5–19.1 cm | F |
| 19.1–21.6 cm | FF |
| 21.6–24.1 cm | G |
| 24.1–26.7 cm | GG |
| 26.7–29.2 cm | H |
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | E |
| 14.0–16.5 cm | F |
| 16.5–19.1 cm | G |
| 19.1–21.6 cm | H |
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | E |
| 14.0–16.5 cm | F |
| 16.5–19.1 cm | G |
| 19.1–21.6 cm | H |
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | DD |
| 14.0–16.5 cm | E |
| 16.5–19.1 cm | F |
| 19.1–21.6 cm | FF |
| 21.6–24.1 cm | G |
| 24.1–26.7 cm | GG |
| 26.7–29.2 cm | H |
| Bust − underbust difference | Cup label |
|---|---|
| 0.0–1.3 cm | AA |
| 1.3–3.8 cm | A |
| 3.8–6.3 cm | B |
| 6.3–8.9 cm | C |
| 8.9–11.4 cm | D |
| 11.4–14.0 cm | E |
| 14.0–16.5 cm | F |
| 16.5–19.1 cm | G |
| 19.1–21.6 cm | H |
A cup size chart translates the difference between your bust and underbust into a cup letter. Measure both, subtract, and the table below tells you which letter that difference means — in inches or centimetres, for six sizing systems.
The chart switches per system because cup ladders genuinely differ: the step that the UK calls DD is labelled E in EU, FR/ES and JP sizing. Any cup size chart that claims one global ladder is quietly wrong.
Quick answer
A cup size chart maps the bust minus underbust difference to a cup letter: roughly one letter per inch (2.5 cm) of difference. A 1-inch difference is an A cup, 3 inches a C, 5 inches a UK DD or an EU E. Each sizing system keeps its own ladder, so this chart is shown per system.
6
sizing systems (US, UK, EU, FR/ES, AU/NZ, JP)
460+
charted sizes with bust ranges
2
measurements needed (underbust + bust)
The cup size chart, per system
The table below lists each cup letter with the difference range it represents. Switch the system tab to see how the same difference is labelled elsewhere. Notice the divergence after D: the UK inserts DD before E, the US uses DD then DDD, and the continental systems walk single letters only.
This per-system structure is the honest way to build a cup size chart. The volume step between B and C is the same body change everywhere — only the naming drifts by market.
How to use this cup size chart
Take your bust measurement at the fullest part and your underbust just below the bust, both level and relaxed. Subtract the underbust from the bust and find that difference in the left column; the row gives your cup letter. An underbust of 32 in with a bust of 35 in leaves a 3-inch difference — a C cup in every ladder shown here.
The cup is only half a size: pair the letter with the band your underbust resolves to (the bra size chart handles that half). A cup letter alone is like a shoe width without a length — technically meaningful, practically incomplete. Pair the halves and the cup size chart finishes the sentence.
Why cup letters are differences, not sizes
A cup letter encodes how much your bust exceeds your underbust — a relationship, not an absolute. That is why a 32D and a 38D are different volumes despite sharing a letter: the same difference over a wider ribcage is more tissue. The cup sizes guide unpacks this with examples.
It also means cup letters compress when the band changes. Stepping from a 34C to a 32D keeps nearly the same volume — the sister-size trick that makes cup size chart reading so much more useful than memorising one letter. Read the cup size chart in trades and it shrinks to a ruler.
Measuring the difference correctly
The cup size chart is only as good as the two measurements behind it. Keep the tape level at the fullest part for the bust and snug under the root for the underbust; a tilted tape or a padded bra shifts the difference by a full letter. The measuring guide covers both positions step by step, and the cup bra measurement page focuses on exactly this pair of readings. The cup size chart can only judge the inputs you give it.
If your difference lands near a boundary in the chart — say 2.4 inches between B and C — treat both letters as candidates. The fit on your body settles it: gaping says smaller, spilling says larger.
Specific cups, specific pages
Each letter deserves its own briefing because the practical questions differ: an A cup's challenge is usually gaping, a D cup's is wire width. We maintain dedicated pages for A, B, C, D and E cups, each with band combinations, sister sizes and the measurement relationship for every system. Start from the cup sizes guide to browse them all.
Beyond the cup size chart: reading ladders fluently
The fastest way to internalise any cup size chart is to translate ladders, not letters. One step up always means roughly one more inch of difference — whether that step is called C to D, D to DD or D to E depends only on the system alphabet. Once you read steps instead of names, the cup size chart stops being a table to memorise and becomes a ruler you can walk.
Test yourself with the example from earlier: a five-inch difference is UK DD, EU E, JP E. Step down to four inches and every system lands on D. Step up to six and you get UK E, EU F, JP F. Three steps, three systems, one skill — that is the whole cup size chart in motion, and why a cup size chart read in steps travels across every border.
Frequently asked questions
How does a cup size chart work?
It maps the difference between your bust and underbust measurements to a cup letter — approximately one letter per inch, or 2.5 cm, of difference. Find your difference in the chart and read across for your cup. Two measurements plus the cup size chart equals one letter.
What difference is a C cup?
About 3 inches, or 7.5 cm, between bust and underbust. In the cup size chart above, C covers roughly 2.5–3.5 in depending on the system. The cup size chart shows the exact range per system.
Is DD bigger than E?
Depends on the alphabet: in UK sizing DD sits between D and E, so E is larger. In EU, FR/ES and JP sizing there is no DD — the step the UK calls DD is already E. The cup size chart keeps those alphabets from colliding.
Can I use a cup size chart with only my bust measurement?
No. The cup is a difference, so you need the underbust too. A bust of 36 in is a B cup on a 34 band and a D cup on a 32 band. Without the underbust, no cup size chart can pick a letter.
Do cup letters mean the same in every country?
Up to D, mostly. Beyond D the ladders split: UK uses DD, E, F, FF; US uses DD, DDD; continental systems use single letters. That is why this cup size chart is organised per system. Beyond D, a per-system cup size chart is the only honest kind.
How often should I re-check my cup size?
Every six to twelve months or after any body change. Cup differences shift with weight, hormones and fitness — the chart is a two-minute refresher. A cup size chart reread takes seconds once you know your difference.
How do I read two cup size chart systems at once?
Read steps, not letters: one row of the cup size chart equals one inch of difference in every system. UK DD and EU E sit on the same row, so you can translate any letter through its difference.
What cup size chart should plus-size shopping use?
The same one — cup ladders do not change with band. Use the cup size chart for the letter and extend further down the band rows of the bra size chart for larger bands. The cup size chart never changes with band, only with system.
Sources & standards
Every size on this site is cross-checked against these published standards and chart families before it ships.
- 2017
ISO 8559-1:2017 — Size designation of clothes — Part 1: Anthropometric definitions for body measurement
Defines the body measurement points (chest/bust girth, underbust girth) this site measures.
- 2017
EN 13402 (label family) — Size designation of clothes — European size labelling
Basis of the continental EU band ladder (65, 70, 75 …) in 5 cm steps.
- 2023
JIS L 4006:2023 — Sizing systems for foundation garments
Japanese foundation-garment sizing; the label family behind JP cup-first sizes such as C75.
- 2019
KS K 9404 — Sizing systems for foundation garments (Korea)
Korean foundation-garment sizing; referenced while the KR system awaits full verification.
- 2025
Multi-source retail consensus — US, UK, FR/ES and AU/NZ bra size charts (cross-brand average)
Inch-based band rounding, UK double-letter cup ladder, FR/ES +15 offset and AU/NZ dress-size bands.
By Bra Size Calculator ·