Bra size calculator USA | Bra size calculator in inches

Find Your Perfect Fit: The Ultimate Bra Size Calculator Guide

Wearing the incorrect bra size is easier than you think, and it may cause discomfort, back pain, and fit issues with your clothing. Good news! With a bra size calculator, you can find your fit in minutes.


International Bra Size Calculator

Why Bra Size Matters

An ideal bra should:

  • Feel snug but not tight. The band does most of the work!

  • Have cups that fully contain your breasts with no spillage or gaps.

  • Keep straps from digging into your shoulders.

If your bra rides up, the straps slip, or the wires poke you -- it's time to measure bra size again.


How to Measure Your Bra Size at Home?

All you'll need is a soft measuring tape and two measurements:

  • Under bust - Take this measurement closely around your ribcage (right under your bust) 

  • Bust - Take this measurement loosely around the fullest part of your chest (don't squish!).

Tally your numbers in a UK or USA bra size calculator, and voila, your size! 


Bra Size

There are two important parts to bra size: band size, which is also the frame size, and cup size.

Band Size (Frame Size)

Band size (or frame size) relates to the measurement around the torso of the bra band. Band sizes, however, are not the same in different countries, and are labelled small (S), medium (M), and large (L), which represent different band measurements. For a guide of standard measurements, look at the conversion chart below, but note that there will be minor variations across brands.

bra size calculator chart


Cup Size

Cup size is calculated based on the difference in measurement between the band size and measurement of the bust (the fullest size of the chest). This difference will correlate to a letter size (e.g. A, B, C) for cup size. The table below contains a reference to the precise cup size.

cup size chart


Bra Sizing Mistakes

1. Guessing your size - 80% of women wear the wrong size bra! 

2. Measuring over clothing - Always measure on bare skin. You want to get an accurate measurement. 

3. Ignoring sister sizes - If the band feels tight, you can go up a band size, and down a cup size (ex. 34C → 36B).


The #1 Accurate Bra Size Calculator

Our bra measurement calculator considers:

1. Band tightness preference (snug vs loose)

2. Sizing worldwide (US, UK, EU, AU)

3. Sister sizes for flexibility