While these methods can give you a rough estimate of your bra size, keep in mind that they may not be as accurate as simply measuring with a soft tape measure. If possible, it’s best to get measured by a bra expert at a lingerie store, or simply find yourself a measuring tape to ensure you’re getting the most accurate fit.

How should your bra sit?

The band

First up, the band itself. Your under-band provides 80 percent of your bra support, so making sure this fits perfectly is essential. Your band should sit firm and straight across your back on the loosest hook. You should be able to get two fingers at the back of the band but feel a little resistance. If it’s too loose, you need a smaller band size. If you’re struggling to get your fingers in, then you should try the next size up. When buying a bra, make sure your band starts on the loosest hook—this ensures the best support and prolongs the use of the bra as you can tighten the band as it stretches.

The straps

The straps are a key part of your bra, as they help to balance the weight of the bust. You’ll be forgiven for thinking that the tighter the straps are, the more support they provide, but straps should actually sit comfortably on the shoulder with space for two fingers underneath without any pinching or sliding. Be sure to check they are equal on both sides.

The center

Also known as the “center gore,” this is the little bit of fabric nestled snuggly between your boobs. It should sit flat to your breast bone without any room underneath but also not dig into your skin. If you can see a gap, you need to go up in size.

The wires

If you’re testing out a bra with wiring, be sure to check it fits properly. These should follow the natural curve at the base of your breast, sitting in behind the breast tissue. If they’re cutting in or sitting on it or too far below, they won’t do their job, and this is where a large amount of support comes from.

The cups

If all the other elements are adjusted correctly, your cups should be smooth and perfectly molded to the curved line of your breast. Remember the warning signs we mentioned above. Spot any wrinkles or sagging? Then move on. Consider the cup capacity; if your cups are too full or breasts are spilling over, it’s also time to try another size.

And most importantly…

Don’t forget to “swoop and scoop.” You might already be doing it, but it is so important, as it can completely change how your bra looks, fits, and feels on your body. It’s a quick and easy way to position the underwire and cups so that your breasts are properly lifted and supported.

How to do it?

Step 1: Place a hand on your under-band at the bottom of the bra, where the underwire curves at the back. With your opposite hand, reach into the top of the cup and move this hand toward the underwire; your fingers should meet. Now, gently bring all of your breast tissue toward the front of the cup.