At a Glance

  • Sizing of bikini tops generally follows the same system observed in bra sizes. Bikini bottom sizes, on the other hand, are typically labeled the same as standard or classic clothing sizes.
  • To determine your correct bikini size, you need to (1) take accurate measurements of your chest (bust and underbust), waist, and hip circumferences, and (2) calculate your bra size.
  • For the bra size, you need to take measurements of your (1) bust and (2) underbust circumferences. Your underbust is necessary to determine the band size of your bra. A bikini’s cup size is the difference between the underbust circumference and the bust circumference.

How to determine the perfect bikini size

Bikini Top

Sizing of bikini tops generally follows the same system observed in bra sizes. Size labels are made up of a combination of numbers and letters which corresponds to a particular cup size and underbust measurement, respectively. For example, you’re probably familiar with bra sizes like 32B and 36C.

Bikini Bottom

Bikini bottom sizes, on the other hand, are typically labeled the same as standard or classic clothing sizes. Sizes are usually numerical and are based on the measurement of waist and/or hip circumferences. For example, a size 4 or 6 is usually for petite women while sizes 18 and 20 are for those with a curvier built. However, there are swimwear brands that use the best-known international sizing system (e.g., Small, Medium, Large, etc.) to classify their bikini bottom sizes.

International Sizes

Bikini manufacturers are rampant not just in the United States but also in different countries abroad. Hence, it comes as no surprise that many brands also feature sizes based on UK, EU, German, French, and Italian size systems. Usually, the manufacturers have a lot of liberty in deciding what sizing system they will follow and how faithfully they will stick to it. Consequently, sizing is not at all universal and your best tool at getting the right fit when buying from a foreign brand is to refer to the company’s published international conversion chart.

Bikini Sizes

To determine your correct bikini size, you need to (1) take accurate measurements of your chest (bust and underbust), waist, and hip circumferences, and (2) calculate your bra size. Write down your measurements in inches and centimeters. Then, refer to the size chart below to find your corresponding US size. Keep in mind that these are approximations so the fit may still vary.

Standard Size US Size Bust Waist Hips
INCHES CM INCHES CM INCHES CM
S 0 32 78 24.5 60 34 84
2 33 80.5 25.5 62.5 35 86.5
4 34 83 26.5 65 36 89
M 6 36 88 28.5 70 38 94
8 38 93 30.5 75 40 99
L 10 40 98 32.5 80 42 104
12 42 103 34.5 85 44 109
XL 14 45 110.5 37.5 92.5 47 116.5

International Sizes: How to convert correctly

You can convert US bikini sizes to UK, EU, and other foreign sizes with the table below.

US Size UK Size EU/German Size IT Size AU Size
0 4 32 36 4
2 6 34 38 6
4 8 36 40 8
6 10 38 42 10
8 12 40 44 12
10 14 42 46 14
12 16 44 48 16
14 18 46 50 18

Measure bra size correctly

When it comes to bikini sizes, knowing your bra size is very important if you want to find a well-fitting two-piece swimwear. To accomplish this, you need to take measurements of your (1) bust and (2) underbust circumferences.

You’ll need a reliable measuring tape for accurate measurement-taking. You can also use a string or a cord to wrap around the body and just measure it with a ruler afterward. If possible, find another person to help you. Make sure you inhale briefly and hold your breath before measuring. The measuring tape should rest horizontally and loosely; it must not press into the skin. Otherwise, you might get a size that’s too small for you.

From there, you can determine your corresponding band size and calculate for your suitable cup size.

Bikini underbust measurement

Your underbust is necessary to determine the band size of your bra. Measurements are usually taken in inches and are rounded off to the next even number. For example, a 31.5-inch underbust measurement fits a 32-inch band size.

Knowing the underbust circumference is also needed to calculate the cup size.

Bikini bust measurement

A bikini’s cup size is the difference between the underbust circumference and the bust circumference – the highest point of the chest area. Once the values are subtracted, the resulting answer translates to an equivalent letter. For example, a bust measurement of 34 inches and underbust measurement of 32 inches has a difference of 2 inches, which is a B cup.

Types of Bikini Tops

  • Underwired bikini
  • Bandeau top
  • Halterneck bikini
  • Bustier
  • Triangle bikini
  • Push-up bikini

There are several ways to wear and secure a bikini top. Some bikinis come with straps that are tied at the back and behind the neck. Some are equipped with clip closures that are fastened at the back. There are also tops that are designed with a more practical front closure.

Overview of different bra types

Overview of different bra types

Bikini Pants

  • Panty, hipster, hot pants or swim shorts
  • tanga
  • string
  • skirt
  • front bodice briefs

Bikini briefs are either made in one piece like conventional underwear or can be tied or closed at the side.