How to Measure Your Bra Size at Home
Finding a bra that actually fits should not feel like a guessing game. If your straps slip, the band rides up your back, or the underwire pokes your ribs, you are wearing the wrong size. Let’s fix that right now.
Already know your measurements? Jump straight to our international bra-size converter to switch between US, UK, and AUS sizing systems instantly.
3 Steps to Find Your True Size
Grab a soft measuring tape and wear your best-fitting, unpadded bra. Do not measure over thick clothes.
- Measure your band size: Wrap the tape snugly around your ribcage directly under your bust. Keep the tape completely parallel to the floor. If you get an odd number like 33 inches, round up to 34 for a comfortable everyday fit, or down to 32 if you are buying a highly stretchy brand like Victoria’s Secret.
- Measure your bust size: Wrap the tape lightly around the fullest part of your chest, usually at nipple level. Do not pull the tape tight enough to squish your breast tissue.
- Calculate your cup size: Subtract your band size from your bust size. Every inch of difference equals one cup size letter. For example, a 36 inch bust minus a 32 inch band leaves a 4 inch difference. That means you are a D cup.
Brand Quirks and Fabric Stretch
Math only gets you halfway there. You also need to factor in the fabric and the shape of the cups. Unlined lace bras have almost zero stretch, meaning you will often need to go up a cup size compared to your everyday t-shirt bra.
Molded foam cups hold their own shape rigidly. If your breasts are naturally bottom-heavy, a molded cup will gap at the top even if the size is mathematically correct. In that scenario, switch to a balconette or a demi-cup instead of buying a smaller size.
Quick Fit Check
Before you rip the tags off a new purchase, look in the mirror. Swap the bra for a different size or style if you notice any of these issues:
- Hovering gore: The center piece between the cups must sit completely flat against your sternum. If it floats, your cup size is too small.
- Quad-boob: If your breast tissue spills over the top or sides, go up a cup size.
- Arching band: The back band should sit perfectly horizontal. If it rides up toward your shoulder blades, the band is too big and is not providing support.
- Digging straps: Most of a bra’s support should come from the band around your ribs. If your straps are doing all the heavy lifting and leaving red marks, you need a tighter band.
