For parents and teens. Measuring should always be the young person's choice, done in private, by themselves or with someone they are comfortable with. A size is only a number to help find something that fits.
The chart
Find the underbust measurement in the left column, then read across to the bust measurement. The column heading is the cup.
| Band (underbust) | AA | A | B | C | D |
|---|---|---|---|---|---|
| 26 (25–27 in · 64–69 cm) | Under 27 in | 27 in · 69 cm | 28 in · 71 cm | 29 in · 74 cm | 30 in · 76 cm |
| 28 (27–29 in · 69–74 cm) | Under 29 in | 29 in · 74 cm | 30 in · 76 cm | 31 in · 79 cm | 32 in · 81 cm |
| 30 (29–31 in · 74–79 cm) | Under 31 in | 31 in · 79 cm | 32 in · 81 cm | 33 in · 84 cm | 34 in · 86 cm |
| 32 (31–33 in · 79–84 cm) | Under 33 in | 33 in · 84 cm | 34 in · 86 cm | 35 in · 89 cm | 36 in · 91 cm |
| 34 (33–35 in · 84–89 cm) | Under 35 in | 35 in · 89 cm | 36 in · 91 cm | 37 in · 94 cm | 38 in · 97 cm |
For example, an underbust of 28 inches and a bust of 30 inches is a 28B. Larger sizes are on the full UK bra size chart, and plenty of teenagers need them.
How to measure
- Underbust: a soft tape around the ribcage, directly under the bust, level and snug. Round to the nearest even number for the band. Add nothing.
- Bust: around the fullest part, with the tape resting lightly.
- Cup: bust minus band. Under 1 inch is AA, 1 inch is A, 2 is B, 3 is C, 4 is D.
The calculator does the sum. A gentle walk-through for a first measurement is in the first bra fitting guide.
Crop tops and first bras sold by age or dress size
The earliest styles are not sold in band and cup sizes. Crop tops and bralettes for young teens are usually labelled by age (9–10, 11–12, 13–14) or by dress size or S, M, L. Each brand's sizes differ, so use its chart, which is normally based on chest measurement.
| Stage | Typical style | How it is sized |
|---|---|---|
| Very early development | Crop top or vest top | By age or chest measurement |
| Some shape, little volume | Soft first bra or bralette | Age, S/M/L, or small band sizes with AA or A |
| A measurable difference of an inch or more | Non-wired bra with cups | Band and cup |
What each term means is explained in training bras vs first bras.
Things that are different for teens
- Size changes quickly. Re-check every six months. Buy two or three bras at a time, not a drawer full.
- Small bands are harder to find. Many adult ranges start at 32. Teen ranges, and some full-bust brands, start at 28 or 30.
- The band may be small while the cup is not. A slim teenager with a fuller bust might be a 28E or 30F. Those sizes are normal, and full-bust brands make them. Adult ranges that do not stock them tend to put people in a 34B that does not fit.
- Uneven development is common. One side often grows ahead of the other for a while. Fit the larger side.
- Comfort comes first. Soft, non-wired styles are the usual starting point.
Signs it is time for the next size
- The band feels tight on the loosest hook, or leaves red marks
- There is a bulge over the top or sides of the cup
- The bra is being pulled down or adjusted through the day
- It simply feels uncomfortable
Buying guidance is in best first bras for teens.
Frequently asked questions
What is a normal bra size for a teenager?
There is no normal size. Teenagers wear everything from crop tops to full-bust sizes, and development happens at different ages and speeds. The right size is the one that fits now.
Is teen bra sizing different from adult sizing?
No. Band-and-cup sizes work the same way at any age. Teen ranges simply concentrate on smaller bands and cups, and first bras and crop tops are often sold by age or dress size instead.
How often should a teenager be re-measured?
About every six months while developing, or whenever a bra starts to feel tight or leaves marks.
Not measured recently? It takes two minutes.
Open the bra size calculator →