34A Bra Size – Measurements And Sister Sizes

Smaller bra sizes in the A and B cup sizes are unique because they are common but at the same time uncommon. While the World Population Review states that the most common bra cup sizes are C and D, you will still find enough A cups like 34A bra size out there.

If you are a 34A bra size, you have a unique bra measurement often seen as larger than it is (due to the band size), but it still falls under small cup A.

So, what’s 34A bra size all about? Is it big or really small?

You can read on to find out everything you need to know about 34A bra size.

What does 34A bra size mean?

34A bra size means the measurement of your bra. It is a twin-component consisting of your band size and cup size. The band number is in numbers, while the cup size is in letters.

Therefore, your band size (in inches) is a circumference measurement of the underbust along the ribcage. The tape is tightly fitted horizontally around the ribcage under the breast. The number is usually rounded up to the next even number.

Some measuring standards also add the +0, +3, or +4 and +5 (for even and odd measurement) methods to get band size. The number for the band size is usually based on the brand or store where you are buying a bra.

You can also get your band measurement over your bust. This is measuring just above the bust and at the edge of the armpit. The number you get should be rounded up to the nearest even number.

Meanwhile, to get cup size, you need the circumference measurement of the bust/breast at the peak fullness (around the nipples). The difference in bust and band sizes makes the cup size.  

This measurement scale, however, is for the US scale. Some international numbers use centimeters instead of inches in arriving at their numbers.

Nonetheless, the 34A bra size falls under the smaller bust with a wide band, so it is seen as small. However, it’s not the smallest for an adult. That’s AAA.

SEE: What Is The Smallest Cup Size Of Bras For Women?

Is 34A bra size really flat?

34A bra cup

It’s not entirely flat.

While 34A bra size does fall under small, it’s not entirely flat. The bust swells about an inch at the peak fullness (around the nipple). The number can be a little over or under an inch. Most points are approximated to whole numbers.

However, it will be little visible under clothes. This depends on what you are wearing; tight-fitting clothes will curve the swell, while free-size or oversize swallows the cup or bulge.  

What is 34A bra size in cm?

73-77 centimeters (cm).

The number is always changing depending on the size chart you are using. The European and International charts provide different numbering systems in centimeters. However, most centimeter measurement comes in 75A.

What are 34A bra size equivalents?

There are different scales for measuring bras. Therefore, the varying numbers and figures. If you want an equivalent to the US size 34A bra, you will have Australia at 12A, the UK at 34A, and Europe and International sizes at 75A.

SEE: The Full List Of Bra Cup Sizes From Smallest To Biggest

What is the sister size of the 34A bra size?

Sister sizes are alternative sizes with the same cup volume. The sizes are related by volume; they fit the same when you wear a bigger or smaller cup.

Sister sizes help to create volume or reduce the look of the bust. It’s like a magic trick women use when they can’t find their actual sizes or want to create an illusion.

When picking a sister size, if you are going up a cup, you are going down a band, and if you are going down a cup you are going up a band.

Therefore, the sister sizes of 34A size are 32B and 36AA bra sizes.

SEE: Best Makeup Kit in All Sizes You Could Possibly Want

34A and 34B size difference

34A and 34B sizes are quite different from one another. A major difference is the cup size.

34A bras have a smaller cup (A), while 34B has an inch larger cup (B). While the band can fit the same, the cup will be smaller or bigger than the actual bust size.

Alternatives and equivalents are better when getting other sizes asides from 34A.


Why are bra sizes inconsistent?

There is no standard fit.

Even though bra sizes are measured using specific proportions and calculations, there are differences in fits. Some bands may fit one and not the other, especially the larger and smaller cups.

Furthermore, the calculations and measuring scales differ. Therefore, it is best to get a custom fit tailored for you to get a perfect bra fit.

Are 34A sports bras available?

Yes, they are.

34A bra size is available for different types of bras, including sports bras. You can also get bralettes, soft bras, T-shirt bras, and demi cups.

Is a 34A bra small?

Yes, it is.

The bra size falls on the smaller spectrum of the bra size chart. It may look small or medium depending on body proportion.

For instance, a flat and slim waist makes the bust more visible and bigger. However, wide hips and waist make the breast look small.

Is 34A a good size?

A size with 34 inches band line is seen as a good size. An adult with this measurement is slim at the top, making the dress fit perfectly.


34A is a small bra size, but it’s not the smallest. The bra size is not that uncommon, and you can get your size alternatives with other measurements. However, if you want to create an illusion, you can use sister sizes for a larger or smaller effect.

Moreover, busts with this size like this can opt out of using bras because it is small enough to get away with it.

Thanks for reading.

Africana Fashion provides helpful guides on bras and measurements.