Bralette Sizing: How to Measure Yourself at Home

Quick answer

Measure your underbust snugly and your full bust loosely with a soft tape, then compare the two numbers to choose a bralette size. If you are between sizes, size up for comfort, because a bralette should sit flat against your ribcage without digging or riding up. Recheck the band first, since band size vs cup size matters less in a soft bralette than a secure, level band.

A bralette is not a bra, so measuring for one follows different logic. You still need two numbers, but the band does most of the work: it should sit level and stay put, while the fabric across the bust stays smooth instead of pulling or gaping.

This guide walks through a simple at home bra measurement you can do in a few minutes with a soft measuring tape, then shows how to read a bralette size chart and run a bralette fit check before you commit to a size.

What you need before you start

Use a soft measuring tape, the kind that bends, not a stiff builder's tape. If you do not have one, a piece of string and a ruler works: wrap the string, mark where it meets, then lay it flat against the ruler. Wear a thin, unpadded bralette or no top at all so the tape can sit against your skin.

Stand in front of a mirror if you can. It helps you keep the tape level around your back, which is the most common place for a measurement to go wrong. Keep the tape snug but not tight, and breathe normally rather than holding your breath.

• Soft tape or string plus ruler
• Thin bralette or no top
• Mirror to check the tape stays level

How to measure your band size

Wrap the tape around your ribcage, directly under your bust, and keep it parallel to the floor. Pull it snug, the way a band would sit, then exhale and read the number in inches. This is your underbust measurement, and it is the starting point for band size.

If the number is even, that is usually your band size. If it is odd, round up to the next even number for a softer fit, or down if you prefer a closer band. Write the number down rather than trusting memory.

• Keep the tape level all the way around your back
• Measure on the exhale, not a deep breath in
• Round odd numbers up for a more comfortable band

How to measure your bust

Wrap the tape around the fullest part of your bust, usually across the nipple line, and keep it level with the floor. Do not pull tight here; the tape should rest against the fabric or skin without compressing. Read the number in inches, then subtract your band measurement from it.

The difference is your cup estimate, and it is only a starting point for a bralette. Soft bralettes often fit more forgivingly than structured bras, so treat the cup number as a guide rather than a rule.

• Keep the tape loose across the bust, not tight
• Measure the fullest point, not the top of the bust
• Subtract band from bust for a cup estimate

Reading a bralette size chart

Most bralette size charts use band and cup together, such as S, M, L or a numbered band with a cup letter. Find your band measurement on the chart first, then check the cup range next to it. If your bust lands between two cup ranges, choose the larger size for a smoother fit.

A bralette size chart is a starting point, not a guarantee. Different fabrics stretch differently, so check the product details for stretch and support level before you decide. For example, the Square Neck Bralette is made from silky-soft micromodal with gentle stretch and gentle, low-impact support, which means it will feel more forgiving than a structured bra.

• Match band first, then cup range
• Size up when you are between cup ranges
• Check the fabric description for stretch and support

The at-home fit check

Put the bralette on and fasten it on the loosest setting, then run a finger under the band. It should sit flat against your ribcage without digging in or lifting away. Raise your arms overhead and twist gently; if the band rides up, the size is too loose, and if it leaves deep marks, it is too tight.

Next, check the cups or front panel. The fabric should lie smooth against your bust without gaping at the top or cutting in at the sides. Adjustable straps should sit flat on your shoulders without slipping, and the center should rest against your chest rather than floating away.

• Band stays level when you raise your arms
• No gaping at the top of the cup
• Straps sit flat without slipping or digging

When to size up or down

Size up if the band leaves red marks, the fabric pulls across the bust, or you feel pressure on your ribcage after an hour. Size down if the band rides up, the straps fall off your shoulders, or the front panel gaps when you move. Small adjustments matter more in a bralette than in a structured bra.

If you are between sizes and want a relaxed, sleep-friendly fit, size up. If you want a closer, more supportive feel for daytime wear, stay with your measured size and rely on the adjustable straps to fine-tune the fit.

• Size up for pressure marks or pulling
• Size down for a band that rides up
• Use adjustable straps to fine-tune between sizes

Your five-step bralette measuring routine

1. Step 1: Measure your underbust: Wrap a soft tape snugly under your bust, keep it level, exhale, and read the number in inches. Checkpoint: the tape should feel like a band, not a belt.
2. Step 2: Measure your full bust: Wrap the tape around the fullest part of your bust without pulling tight, and read the number in inches. Checkpoint: the tape stays level around your back.
3. Step 3: Find your size on the chart: Match your underbust to the band range, then check the cup range next to it and size up if you are between ranges. Checkpoint: band first, cup second.
4. Step 4: Try the bralette on: Fasten on the loosest setting and check that the band sits flat and the front panel lies smooth. Checkpoint: no digging, no gaping, no riding up.
5. Step 5: Adjust and reassess: Tighten or loosen the adjustable straps, move around, and see how the band behaves after a few minutes. Checkpoint: if the band still rides up or digs in, change size, not just the straps.

How NUNE bralette sizing fits into your measurements

• Square Neck Bralette: Made from silky-soft micromodal with extra-soft underbust elastic and adjustable soft straps for gentle, low-impact support. The soft underbust elastic and adjustable straps let you fine-tune the band, so your measured size has room to work without digging.
• Triangle Bralette: Cut from a silky-soft micromodal blend with a double-layered modal construction, adjustable straps, and a flattering low neckline. The double-layer front gives a bit more coverage across the bust, which helps if you are between cup sizes and want a smoother line.
• High Waist Brief: Made from silky-soft micromodal with generous stretch, a high-waisted full-coverage fit, and smooth folded edges. The same stretch fabric logic applies to bottoms, so if your bralette size sits at the edge of a range, matching the brief in the same size keeps the set consistent.

Measuring for a bralette takes a few minutes and saves you from guessing. Start with your underbust and full bust, check the size chart, then trust the fit check over the number on the label. If you are between sizes, size up for comfort and use the adjustable straps to dial in the band.