Bra Size Calculator — Underoutfit

Underoutfit — Fit Guide

Find Your Perfect
Bra Size

Three measurements. Thirty seconds. A size that actually fits — and a bra designed around it.

★ 4.8 / 5 Rating 180-Day Fit Guarantee Sizes 30A – 46H
1
Underbust
2
Bust
3
Preferences
4
Your Size

Step 1 of 3

Measure Your Underbust

Wrap a soft measuring tape around your ribcage, directly below your breasts. Take three readings — loose, snug, and tight — on a deep exhale. All measurements should be taken on bare skin.

Tape sits loosely — no digging in

in

Tape snug — as tight as a well-fitting bra band

in

Tape as tight as possible without discomfort

in

How to measure your underbust

1

Loose

The tape should not dig in at all. Let it rest naturally around your ribcage.

2

Snug

Dig the tape in a little — as snug as you'd want a bra band to feel during wear.

3

Tight

Pull the tape as tight as possible without causing pain or discomfort.

① LOOSE ② SNUG ③ TIGHT ① LOOSE ② SNUG ③ TIGHT FRONT VIEW SIDE VIEW

Measure on bare skin, on a deep exhale. Keep tape parallel to the floor.

Please enter all three underbust measurements before continuing.

Step 2 of 3

Measure Your Bust

Wrap the tape loosely around the fullest part of your bust. Take three readings in different postures — standing, leaning forward at 90°, and lying flat on your back.

Stand straight, tape loosely around fullest part

in

Bend forward 90°, tape loosely around fullest part

in

Lie on your back, tape loosely around fullest part

in

How to measure your bust

4

Standing

Stand straight and measure loosely around the fullest part of your bust.

5

Leaning

Bend forward at 90° and measure loosely around the fullest part.

6

Lying Down

Lie on your back and measure loosely around the fullest part of your bust.

④ STANDING UPRIGHT ⑤ LEANING BENT FORWARD 90° ⑥ LYING DOWN FLAT ON BACK

Keep the tape parallel to the floor and loose enough to slip two fingers underneath.

Please enter all three bust measurements before continuing.

Step 3 of 3

Your Preferences

Choose your preferred sizing system and units. These settings affect how your result is displayed — the underlying fit calculation remains the same.

Sizing System

Units Used for Measurements

Your Recommended Size

Fit Tips for Your Size

Shop Your Size

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Multi-measurement method
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