Step one: Find a measuring tool

First, you will need a long, soft measuring tape. If you don’t have one, you can use a piece of string or ribbon instead. If you’re using string or ribbon, you’ll mark the length of your measurement with a marker or piece of tape, then use a ruler or hard measuring tape to measure the length of the string or ribbon to the dot.

Step two: Dress accordingly

Before taking your measurements, ensure you’re wearing a non-padded, wireless bra. Avoid bras with heavy padding or compression, such as sports bras, as they can lead to inaccurate measurements.

Step three: Measure your underbust

To determine your underbust size, place the measuring tape directly under your bust. Keep the tape level and snug, but not too tight or too loose. Round your measurement to the nearest whole number, and record it.

Write this number down

Step four: Measure you bust

Next, measure around the fullest part of your chest to find your cup size. Keep the tape straight across your back, and round to the nearest whole number.

If your breasts have a drooping shape, position the tape lower, near the tip of your bust, to capture the entire area. For uneven breasts, measure the fullest side, extending to the middle of your back, and double that number.

Write this number down

Step five: Find your cup size

Cup sizes vary by brand and country. To find yours, subtract your underbust measurement from your bust measurement. Use the chart provided to identify your correct cup size.