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The fit guide No. 210
How do I measure my bust correctly?
Measure the fullest part of the bust without flattening it, then compare it with the underbust to find the cup.
Lace Index — 2,491 lingerie styles, S–3XL, selected 4XL, $9.90–$47.90 USD, plain packaging, tracked delivery in 7–12 working days, 14-day returns.
Measure first, then choose the shape. Between sizes, take the larger.
Match the piece to the outfit, the light and how long you will wear it.
Plain packaging, tracked delivery and 14-day returns with the seal intact.
The bust measurement is the distance around the fullest part of your chest, usually across the nipple line; Lace Index stocks 2,491 sexy lingerie styles in S–3XL, with selected 4XL, and each product page lists the exact sizes in stock. On its own it does not give a bra size; it only becomes a cup when you compare it with the underbust. Measure both, then use the difference. The product page shows the sizes held for that style, which may be narrower than the full chart.
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Pieces for this answer.
01
Prepare the tape
Stand relaxed with your arms down and use a soft tape. Wear an unpadded bra or nothing. Keep the tape level at the front and back; if it slopes, the number will be too high or too low. Do not press the tape into the bust or let it sit loose.
02
Measure the fullest point
Wrap the tape around the fullest part of the bust, usually across the nipple line. Keep it parallel to the floor. Read the number in centimetres and repeat the measurement. If one side is larger, measure across the larger side; bras can be adjusted with the strap on the smaller side.
03
Work out the cup
Subtract the underbust from the bust. A difference of about 10 cm is around an AA, 12.5 cm an A, 15 cm a B, 17.5 cm a C, 20 cm a D and 22.5 cm a DD. These are starting points, not a guarantee: cup fitting varies by brand, style and the amount of stretch in the fabric. Use the product page and the size guide together.
04
Check the cup on the body
The cup should sit flat against the breast without gaping at the top or cutting across the top. The centre front should lie close to the body. If the cup wrinkles, it may be too large; if the breast spills over the top or sides, it may be too small. Between two cups, try the larger cup with the same band and check the straps.
05
What you need before you start
Use a soft tape, a mirror and an unpadded bra or bare skin. Stand relaxed with your arms down, breathe normally and keep the tape level all the way around. Ask someone to help if the tape twists at the back. Measure in centimetres or inches, but stay in one unit for both the bust and the underbust so the difference is comparable.
06
Where the tape should sit
The bust tape goes around the fullest part of the chest, usually across the nipple line. It should be parallel to the floor, not pulled up under the arms and not pressed into the breast. Keep the tape snug enough to stay in place but loose enough to slide one finger underneath. Read the number at the front, then repeat the measurement once to check it.
07
Turning two numbers into a size
Subtract the underbust from the bust. A difference of about 10 cm is around an AA, 12.5 cm an A, 15 cm a B, 17.5 cm a C, 20 cm a D and 22.5 cm a DD. Treat this as a starting point: cup depth, wire shape and fabric stretch vary between styles. Use the size chart for the band and the product page for the sizes actually held.
08
If the numbers look wrong
A measurement that changes by more than 2-3 cm usually means the tape moved, the arms were raised, or the tape was pulled too tight. Measure again in front of a mirror with the tape level. If one side is larger, measure across the larger side and adjust the strap on the smaller side. Do not choose a band size from a dress size.
09
Measuring for a specific style
A plunge, balconette, full-cup and strapless bra use the same two measurements but different coverage. A full-cup style needs enough room at the top of the cup; a strapless style needs a firmer band. Check the product page for the exact sizes and the fit notes for that shape before you order.
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At a glance
| Category | Bras & Sets |
|---|---|
| Price | From $9.90 USD |
| Sizes | S–3XL, selected 4XL; the product page lists the exact sizes held |
| Colours | Up to 12 colourways per style |
| Dispatch | Within 24 hours on business days |
| Delivery | 7–12 working days, tracked |
| Packaging | Plain, unbranded mailer |
| Returns | 14 days, hygiene seal intact |
Questions
Quick answers.
How do I measure my bust correctly?
Should I measure with a bra on?+
Use an unpadded bra or bare skin. A padded bra adds volume that is not yours.
What if one breast is larger?+
Measure across the larger side. Tighten the strap on the smaller side to even the line.
Is the cup size the same in every brand?+
No. Cup fitting changes with the brand, the style and the stretch in the fabric. Check the product page.
Can I use my dress size instead?+
No. Dress size does not describe the bust or the underbust. Use the measurements.
What is the difference between a B and a C cup?+
About 2.5 cm of bust circumference on the same band, but always check the actual fit.
Should I measure in centimetres or inches?+
Either works. Use the same unit for the bust and the underbust, and convert only when you compare with a chart.
Why is my bust measurement different in a shop?+
Posture, the bra you are wearing and how tight the tape is all change the number. Measure the same way twice at home and use that repeatable number.
Do I need a helper?+
Not always, but a second person keeps the tape level at the back and gives a more consistent reading.
Still unsure?
Send us your measurements.
Tell us the piece you are considering and the fit you want. We will compare it with the actual stock.