UK Bra Size Chart | Band & Cup Size Guide

UK Bra Size Chart

A UK bra size combines two parts: a band size, such as 30, 32, 34 or 36, and a cup size, such as C, D, DD or F.

Use the UK bra size chart below to match your band size with the difference between your full bust and band measurements. The result gives you a useful UK starting size to try.

If you do not know your measurements yet, follow our How to Measure Bra Size guide.

If you already have your measurements and want an automatic result, use our Bra Size Calculator UK.

How to Use the UK Bra Size Chart

You need two measurements:

1. Underbust measurement — measure snugly around your ribcage directly underneath your bust.
2. Full bust measurement — measure around the fullest part of your bust, keeping the tape level and comfortable.

Then:

1. Determine your starting UK band size from your underbust measurement.
2. Subtract your actual underbust measurement from your full bust measurement.
3. Find your band size in the left-hand column of the chart.
4. Find the bust-to-band difference across the top.
5. Where the row and column meet is your estimated UK bra size.

For example, if you have a 34-inch band and a 38-inch full bust, the difference is 4 inches:

38 − 34 = 4 inches

On the chart, a 34 band with a 4-inch difference gives a starting size of 34D.

UK Bra Size Chart (Simplified)

Difference = Full Bust − Actual Underbust Measurement

This is a simplified starting-size chart. Bra sizing and fit can vary between brands, styles and individual bodies, so the size shown should be treated as a starting point rather than a guaranteed fit.

If you measure in centimetres, you can either convert your measurements to inches or enter them directly into our UK Bra Size Calculator.

UK Cup Size Progression

UK cup sizing does not always move through single letters in alphabetical order.

A common UK progression is:

A → B → C → D → DD → E → F → FF → G → GG → H → HH → J → JJ → K → KK → L

This means that after a D cup comes DD, followed by E. After F comes FF, and after G comes GG.

The exact size range available will depend on the bra brand and style, but understanding the UK cup sequence is especially important when comparing UK sizes with US or European sizing systems.

If you want to understand why UK bands and cups work this way, read How UK Bra Sizes Work.

Example: How to Read the UK Bra Size Chart

Suppose your measurements are:

• Band: 34 inches
• Full bust: 38 inches

First calculate the difference:

38 − 34 = 4 inches

Now find:

• the 34 band row; and
• the 4-inch difference column.

They meet at:

34D

So 34D would be your UK starting size.

You can then try that size and check whether the band and cups fit correctly.

If you would rather not calculate the difference yourself, enter your measurements into the Bra Size Calculator.

Band and Cup Sizes Work Together

A bra size should be read as a complete size rather than treating the cup letter separately.

For example:

34D means a 34 band combined with a D cup.

The cup letter is relative to the band size, so a D cup is not one fixed cup volume across every band.

For example, 34D and 38D are not the same cup volume. As the band size changes, the cup volume associated with the same letter also changes.

This relationship is why sister sizes exist. Sister sizes use different band and cup combinations while keeping a similar cup volume.

For example, moving to a larger band usually means moving down one cup step to stay within a similar cup volume.

You can see the full relationship in our UK Bra Sister Sizes guide and chart.

For a deeper explanation of band sizes, cup sizes and UK cup progression, read How UK Bra Sizes Work.

What If Your Chart Size Doesn’t Fit?

A bra size chart gives you a starting point based on your measurements. It cannot guarantee that every bra labelled with that size will fit identically.

If your starting size does not feel right, check these three things.

1. Recheck Your Measurements

Even a small difference in how the tape is positioned or tightened can affect the result.

Your underbust measurement should be level and snug, while your full bust measurement should follow the fullest part of the bust without compressing it.

See Common Bra Measuring Mistakes if your calculated size looks very different from the size you expected.

2. Check the Band and Cups Separately

A bra may be the wrong fit even when the label appears to match your calculated size.

Check whether:

• the band sits level around your body;
• the band feels firm without being painfully tight;
• breast tissue is fully contained within the cups;
• the cups are not noticeably gaping or causing overflow;
• the straps feel secure without doing all of the supporting work.

If something is wrong, use our Bra Fit Problems guide to identify the likely cause.

3. Consider a Sister Size

Sometimes the cup volume feels right while the band feels too tight or too loose.

In that situation, a sister size may give you a better combination of band and cup while keeping a similar cup volume.

See our Bra Sister Sizes guide to find the sizes next to yours.

UK vs US and EU Bra Sizes

A UK bra size should not automatically be treated as the same size in every country.

Band labels, cup progression and size conventions can differ between UK, US and European sizing systems.

This becomes particularly important in larger cup sizes because UK sizing uses cup labels such as DD, FF and GG, while another sizing system may use a different label for a comparable size.

If you are buying from an international brand or retailer, check the sizing system being used rather than relying only on the cup letter.

See our UK vs US vs EU Bra Sizes guide for more help comparing the systems.

UK Bra Size Chart FAQs

What is a UK bra size chart?

A UK bra size chart shows how a band size and cup size combine to form a complete UK bra size, such as 32C, 34D or 36DD.

The band relates to the measurement around the ribcage underneath the bust, while the cup is estimated from the difference between the band and full bust measurements.

How do I find my cup size on the chart?

Measure your full bust and subtract your band measurement.

The difference is then matched to a cup step on the chart.

For example:

38-inch bust − 34-inch band = 4-inch difference

On this chart, a 4-inch difference corresponds to a D cup, giving a starting size of 34D.

Why does the UK use DD, FF and GG cup sizes?

UK bra sizing commonly uses double-letter cup steps as the cup range increases.

For example:

D → DD → E → F → FF → G → GG

This is different from some international sizing systems, which is why a UK cup letter should not automatically be treated as the equivalent US or EU cup letter.

Is a 34D the same cup size as a 38D?

No. Cup letters are relative to band size.

A 38D has more cup volume than a 34D. This is also why two different bra sizes can sometimes have similar cup volumes when the band and cup are adjusted together through sister sizing.

Read our Bra Sister Sizes guide for examples.

Can I use this chart if I measured in centimetres?

Yes, but this simplified chart is shown in inches.

You can convert your measurements into inches before using the table, or enter your measurements in centimetres directly into our Bra Size Calculator, which can handle the conversion for you.

What if I am between two bra sizes?

Start with the closest calculated size and assess the fit of the band and cups separately.

Depending on your measurements, body shape, bra construction and personal comfort, you may prefer a nearby size or sister size.

The calculated result is best used as a starting point for trying and checking fit.

Calculate Your UK Bra Size

If you know your underbust and full bust measurements, you do not need to work through the chart manually.

calculate your UK bra size to enter your measurements and calculate your UK starting size automatically.

The calculator can also help you explore sister sizes and international size equivalents after you receive your result.