Cup Size Comparison
What Each Size Looks Like (A to H)
See how bra cup letters relate to one another — from A through H — with a simple, illustrated comparison built for easy, body-positive understanding.
Not Sure Where You Start?
Use the free Bra Size Calculator for a simple band and bust estimate before you compare sizes below.
What Does Cup Size Comparison Mean?
A cup size comparison shows how bra cup letters relate to one another, from A through H. Each letter stands for roughly one extra inch of difference between your bust and band measurement. As the letters move forward, the cup holds more fullness. This guide gives you a simple, visual starting point — not a final or guaranteed size.
Key Takeaways
- Cup letters compare the gap between your bust and band measurement, not your body size.
- Each letter generally adds about one more inch to that gap.
- The same cup letter can look different on different band sizes.
- A bra size only makes full sense with both the band number and the cup letter together, like 34C.
- This chart is a simple estimate — your best fit can still depend on style, brand, and your own shape.
Note: This guide is for general education and comparison. It does not replace a real fitting, and it is not medical advice.
How Cup Letters Work
Bra cup letters are based on the difference between your bust measurement and your band measurement — not the size of your body. A one-inch difference is usually an A cup. Add about one more inch for each letter after that, all the way through H. This gap is what a cup size comparison is really about. It compares the gap, not the body.
Because of this, the same cup letter can look different on different band sizes. A bra cup size comparison only makes full sense when you also know the band number next to it, like 34C or 36D. A 32D and a 38D share the same four-inch gap, but the 38D generally holds more fullness because the band itself is bigger.
Ready to find your own numbers? Try the free Bra Size Calculator for a simple band and bust estimate.
How to Measure Your Bra Size in 3 Steps
A simple tape measurement is the easiest way to find your starting point before using the chart below. Do this without a bra, standing, with a soft tape measure.
Measure Your Band
Wrap a soft tape snugly around your ribcage, just under your bust. Keep it level all the way around, and breathe out normally before reading the number.
Measure Your Bust
Stand with your arms relaxed at your sides. Wrap the tape around the fullest part of your bust, keeping it level and snug, but not pulled tight.
Find the Gap
Subtract your band number from your bust number. That gap, in inches, points to your cup letter — match it against the chart below.
Want this done for you automatically? Use the free Bra Size Calculator.
Cup Size Comparison Chart (A to H)
Here is a simple breast cup size comparison chart. The gap is the approximate difference between your bust and band measurement.
| Cup Letter | Approx. Gap | General Look | Good Starting Point For |
|---|---|---|---|
| A | ~1 inch | Sits close to the chest, soft curve | Bralettes, light everyday tops |
| B | ~2 inches | Light, gently rounded shape | Demi-cup, lightly lined styles |
| C | ~3 inches | Fuller, clearly rounded shape | Balconette, T-shirt bras |
| D | ~4 inches | Noticeably fuller, stronger curve | Full-cup styles with good support |
| E | ~5 inches | More fullness, needs steady support | Full-coverage, wider-strap styles |
| F | ~6 inches | Fuller, rounder, benefits from firm support | Full-cup wire styles |
| G | ~7 inches | Fuller shape, may feel heavier by day's end | Wider straps, sturdy full-cup styles |
| H | ~8 inches | Fullest shape in this range | Specialist full-coverage styles |
These are general estimates to help you compare sizes. Your best fit can still depend on bra style, brand, and your own body shape.
Want a deeper breakdown of band sizes too? Visit our Size Guides.
Relative Fullness at a Glance
This bar shows relative fullness only, not an exact measurement. It is here to help you compare A through H side by side, at a glance.
What Does Each Cup Size Look Like?
A simple, illustrated look at A through H, side by side.
Ready to compare your own size? The Bra Size Calculator gives you a free, simple estimate.
Side Profile at a Glance
A simple illustrated curve for each cup size, showing how the shape generally grows from A to H. These are illustrations only, not photos — scroll sideways on mobile.
Sister Sizes: Same Fullness, Different Band
A sister size is a different bra size that holds a similar amount of fullness, just with a different band size. If your usual size feels almost right but the band feels slightly loose or tight, a sister size can be a helpful next step to try. Sister sizing works alongside the comparison chart above — it changes the band, not the overall fullness.
Shown on a 32 inch band as an example. The same idea works on any band size.
Learn more about sister sizing in our Size Guides.
Common Bra Fit Problems
Every cup size can feel different depending on the bra style, the brand, and your own body shape. Here are common signs, what they usually mean, and a simple next step.
For a full walkthrough of fit signs, see our Size Guides.
Cup Size Myths That Won't Die
A few common ideas about cup size — and what is actually true.
"Understanding your size should feel simple, not stressful."
FitMyBra builds simple, body-positive guides for sizing, comfort, and everyday support. This page compares cup letters side by side so you can start with confidence — not pressure.
Cup Size Comparison FAQ
A few common questions about cup letters, bra size, and sister sizing.
Find Your Size. Then Compare With Confidence.
Use FitMyBra to understand sizing, cup fit, and everyday comfort.