How to measure your bra size at home (properly)

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Most people wear the wrong bra size, usually a band that's too big and cups that are too small. The good news: you can get much closer to your real size in five minutes with a soft tape measure. Here's how.

What you need

• A soft tape measure (or a piece of string and a ruler)
• A mirror
• A non-padded bra you already own, or no bra

Step 1: Measure your band

Wrap the tape snugly around your ribcage, directly under your bust, where the band of a bra sits. Keep it level all the way around and breathe out. Round to the nearest whole inch.

If you get an odd number, try the even sizes either side. Bands come in even numbers (30, 32, 34…), and many people prefer the tighter one.

Step 2: Measure your bust

Measure loosely around the fullest part of your bust, keeping the tape level across your back. Don't pull it tight.

Step 3: Work out your cup

Subtract your band measurement from your bust measurement. Each inch of difference is one cup size.

Example: underbust 32", bust 36". The difference is 4", so you'd start at 32D.

Australian bras usually use centimetre-based band sizes (10, 12, 14…). Check the brand's own chart, because naming differs between brands and countries.

Step 4: Check the fit (this matters more than the tape)

• Band: level all the way round, snug on the loosest hook. You should fit two fingers underneath, no more.
• Centre (gore): on an underwire, the centre should sit flat against your sternum.
• Cups: no spilling over the top or sides, and no wrinkling or gaping.
• Wires: should surround breast tissue, not sit on it, at the sides.
• Straps: shouldn't dig in. If they're doing the lifting, the band is too loose.

Sister sizes: your secret weapon

Cup volume is tied to band size. Go down a band and up a cup (or the reverse) and the cup volume stays about the same. So if the band feels loose but the cups fit, try a sister size:

When to re-measure

Re-check your size every 6–12 months, and after weight changes, pregnancy or starting a new training routine. Bodies change, and so do sizes.

Ready to shop?

Once you know your size, see our picks for the best seamless bras.