How to Measure Yourself for a Push Up Bra at Home

Quick answer

Measure your band snugly around your ribcage directly under your bust, then measure the fullest part of your bust. Subtract the band from the bust measurement: about 1 inch means an A cup, 2 inches a B, 3 inches a C, and so on. Do both measurements on bare skin with the tape level, because a padded push up bra adds lift that will throw off your numbers.

A push up bra only lifts well when the band and cup are right. If the band is too loose, the cups ride up and the padding pushes tissue sideways instead of forward. If the cups are too small, you get spillage and the center of the bra lifts away from your chest.

You can get accurate numbers at home with a soft tape measure and a mirror in about five minutes. This guide walks through the order that matters: band first, bust second, then a real-world fit check with the bra on.

Before you start: what you need and what to skip

Use a soft measuring tape, or a piece of string you mark and measure against a ruler. Stand in front of a mirror so you can see whether the tape is level all the way around. Wear a thin, unpadded bra or no bra at all.

Skip measuring over a padded or push up bra. Padding and cushions change the bust measurement, which is exactly the number a push up bra depends on. Also avoid measuring right after a workout or in a hurry with your arms raised, since both can shift the tape.

• Checkpoint: the tape should sit flat against your skin, not compress it.
• If you are between two band sizes, size up and rely on the adjustable hooks.

Step 1: Measure your band size

Wrap the tape around your ribcage directly under your bust, where the bra band will sit. Keep it level with the floor across your back and breathe out normally before you read the number. The tape should feel snug, like a bra band on its middle hook, not tight enough to leave a mark.

Round to the nearest whole inch. If the number is even, add 4 inches; if it is odd, add 5. That total is your starting band size. Most of the support in a push up bra comes from this band, so a band that is too loose is the most common reason lift disappears during the day.

• Common mistake: measuring over a shirt or a padded bra, which adds bulk and inflates the band.
• If the tape dips at the back, your band size will read 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 relaxed, without pulling it tight or letting it sag at the back. Stand straight with your arms down for the most repeatable reading.

Read the number to the nearest whole inch. If your bust is fuller at the sides, take a second reading with the tape slightly higher and use the larger number, since a push up bra needs enough cup depth to contain that tissue rather than press it flat.

• Checkpoint: the tape should touch your bust without indenting it.
• Measure twice. If the two readings differ by more than half an inch, adjust the tape and try again.

Step 3: Work out your cup size

Subtract your band size from your bust size. A difference of about 1 inch is an A cup, 2 inches a B, 3 inches a C, 4 inches a D, and 5 inches a DD or E, depending on the brand. Write both numbers down before you shop so you can compare them against a size chart.

This is where a bra size calculator can help, but treat it as a starting point rather than a verdict. Calculators vary in how they round, and push up styles often run differently from unpadded bras. Use the calculated size to pick two or three candidates, then judge by how the bra actually fits.

• Common mistake: assuming your cup size stays the same when your band size changes.
• If the difference lands between two cups, start with the larger cup in a push up style.

Step 4: Check the fit with the bra on

Fasten the band on the loosest hook, lean forward, and settle your bust into the cups. The band should sit level and stay put when you raise your arms. The center panel between the cups should rest against your chest, and the underwire should follow the base of your bust rather than sit on top of it.

Check the straps last. They should stay put without digging in, and you should be able to slide one finger underneath. Straps that carry the weight are a sign the band is too big. If the cups gape at the top, the cup is likely too large or too shallow for your shape; if tissue spills over, go up a cup.

• Checkpoint: the band should do roughly 80 percent of the lifting work.
• If the band rides up at the back, go down a band size and up a cup.

Step 5: Re-measure when your body changes

Band and cup measurements shift with weight changes, hormonal cycles, and training. Re-measure every six months or whenever a bra that used to fit starts digging, gaping, or sliding. A five-minute check saves you from replacing bras that were never the right size to begin with.

If your measurements fall between two sizes, choose based on the bra's construction. Push up styles with soft cushions inside the cups, like a padded push up bikini top, tend to be more forgiving of a half-size difference than structured underwire bras.

• Common mistake: buying several bras in a new size before confirming one fits.
• Keep one well-fitting bra as your reference when you shop next time.

Your five-minute measuring routine

1. 1. Set up: Stand in front of a mirror with a soft tape measure, wearing a thin unpadded bra or nothing at all. Checkpoint: the tape lies flat and level before you take any reading.
2. 2. Measure the band: Wrap the tape snugly under your bust, breathe out, and read the number to the nearest inch. Add 4 for an even number, 5 for an odd number. Common mistake: pulling the tape tight enough to compress your ribcage.
3. 3. Measure the bust: Wrap the tape around the fullest part of your bust, keeping it level and relaxed. Read to the nearest inch. Checkpoint: measure twice and use the larger number if the readings differ.
4. 4. Calculate the cup: Subtract the band size from the bust size. One inch is roughly an A cup, two a B, three a C, four a D. Treat a bra size calculator as a starting point, then confirm with a real fit check.
5. 5. Try the fit check: Fasten the band on the loosest hook, settle your bust into the cups, and check that the center panel sits flat and the band stays level. If the band rides up, go down a band size and up a cup.
6. 6. Re-measure every six months: Your measurements change with weight, cycle, and training, so repeat the routine twice a year or whenever a bra starts to feel off. Next step: use your numbers to compare two or three sizes before committing.

How real push up styles use your measurements

• push up bra: The Adventuress push up bra is designed to give a deep cleavage without sacrificing comfort, with translucent fine mesh, a spiderweb flock print, and gold lurex woven through the shoulder straps. Because the lift comes from the cup construction, an accurate band and cup measurement keeps the mesh sitting smooth instead of stretching or gaping.
• push up bikini top: The Holi Vintage push up bikini top uses soft cushions inside the cups for extra lift and ties at the neck with an additional strap framing the décolleté. A tie-neck style lets you fine-tune the fit at the neck, so your band and cup numbers matter most for the underbust fit.
• balcony bra: The Dame de Paris balcony bra combines shiny jacquard fabric with gold lurex straps and a gold-plated 'Top Secret' talisman between the cups. A balcony cut covers less of the upper bust than a push up, so the center panel should sit flat against your chest when your cup size is right.

Measure the band snug, measure the bust relaxed, and let the difference point you to a cup size. Then trust the fit check over the number on the label, because a push up bra that stays level and flat at the center will lift far better than one that is simply the size a calculator suggested.