How to Measure Yourself for a Bra That Actually Fits

Quick answer

To measure your bra size at home, wrap a soft tape measure snugly around your ribcage just under your bust for the band size, then measure around the fullest part of your bust for the cup size. Subtract the band measurement from the bust measurement: a 1-inch difference is an A cup, 2 inches is a B, 3 inches is a C, and so on. Always round the band measurement to the nearest even number and re-measure on a second day to confirm consistency.

What you need before you start

A soft, flexible tape measure is essential because a stiff one won't follow your body's curves. If you don't have one, use a piece of string or a ribbon and then lay it flat against a ruler. Wear an unlined, non-padded bra or no bra at all—padding adds volume that throws off your bust measurement. Stand in front of a mirror so you can keep the tape level all the way around. Ask a friend to help if you can; twisting to read the tape yourself can shift it out of position.

Step 1: Measure your band size

Wrap the tape around your ribcage, directly under your bust, keeping it parallel to the floor. The tape should feel snug—not tight enough to leave marks, but not loose enough to slide down. Breathe out normally and read the number where the tape meets. If you get an odd number, round down to the nearest even number (e.g., 33 inches becomes 32). This is your band size. A common mistake is measuring too high, over the bust instead of under it—that gives a band size that's too large and a cup size that's too small.

Step 2: Measure your bust size

Wrap the tape around the fullest part of your bust, usually across the nipple line. Keep the tape level and not pulled tight—it should rest gently against your skin without compressing breast tissue. Stand straight with your arms at your sides. Read the number at the center of your chest. If you're wearing a bra, make sure it doesn't flatten or distort your natural shape. The most common error here is pulling the tape too tight, which reduces the bust measurement and leads to a cup size that's too small.

Step 3: Calculate your cup size

Subtract your band measurement from your bust measurement. The difference in inches determines your cup size: 1 inch = A, 2 inches = B, 3 inches = C, 4 inches = D, 5 inches = DD/E, 6 inches = DDD/F, and so on. For example, a 34-inch band and a 37-inch bust gives a 3-inch difference, so you'd start with a 34C. Keep in mind that cup size is not static—it changes with band size. A 34C has a different cup volume than a 36C, so always use your own two measurements together.

Step 4: Try a test fit (the real proof)

Numbers are a starting point, not a guarantee. Try on a bra in your calculated size and check these five points: the band should sit level and snug around your ribcage—you should be able to fit two fingers under it, but it shouldn't ride up when you lift your arms. The center gore (the piece between the cups) should lie flat against your sternum. The cups should contain all your breast tissue without digging in or gaping. The underwire, if present, should sit on your ribcage, not on breast tissue. The straps should stay put without digging into your shoulders. If any of these fail, adjust the band or cup size accordingly.

When to re-measure

Your bra size can change with weight fluctuations, hormonal cycles, pregnancy, or changes in exercise routine. Re-measure every six months, or whenever your current bras start feeling uncomfortable. A bra that once fit perfectly may now need a different band or cup size even if your weight hasn't changed noticeably. Also note that sizing varies between brands and styles—a 34B in one bralette might feel different in another. Always check the specific brand's size chart and return policy before committing to a new style.

Your at-home bra fit checklist

1. Band check: The band should be snug and level all the way around. You should be able to slide two fingers under it, but it shouldn't shift when you raise your arms. If the band rides up, go down a band size. If it digs in, go up a band size.
2. Cup check: The cups should lie smooth against your breasts with no wrinkling or gaping. Your entire breast should be inside the cup, not spilling over the top or sides. If you see spillage, try a larger cup. If the cup wrinkles, try a smaller cup or a different style.
3. Center gore check: The center piece between the cups should rest flat against your chest. If it floats away or digs in, the cup size or band size is off. A floating gore often means the cup is too small; a digging gore often means the band is too tight.
4. Strap check: Straps should stay in place without slipping off your shoulders or leaving deep marks. You should be able to fit one finger under each strap. Adjust the sliders for comfort. If straps still dig in, the band may be too loose and carrying too much weight.
5. Underwire check (if applicable): The underwire should sit flat against your ribcage, following the natural curve of your breast root—not poking into breast tissue. If the wire pokes or sits on breast tissue, the cup is likely too small or the band too large.

How Tutti Rouge styles apply these measurements

• Gia Bralette : Vibrant Purple: Medium support with powermesh-lined cups, caged cup detailing, and adjustable straps with signature Tutti heart sliders. Powermesh liners add shaping without heavy padding, so your measured cup size is more likely to match the fit you see. Adjustable straps let you fine-tune the lift after you've found your band and cup.