Find Your Perfect Bra Size – Advanced Calculator
Calculate your bra size with Standard 2-point, Victoria's Secret +4, or ABTF 6-measurement methods. Compare US, UK, EU, AU, and FR sizing instantly – free, private, and accurate.
Bra Size Calculator & Fit Finder
Measure snugly under your bust around your ribcage.
Measure around the fullest part of your chest.
34C
34C
75C
12C
90C
Need a different method? Try the Cup Size Calculator or Sister Size Finder.
Explore All Calculators
Fourteen tools covering every sizing method, life stage, and region — pick the one that fits how you want to measure.
Bra Size Calculator
The standard band + bust method, instantly.
Calculate → CORECup Size Calculator
Already know your band? Get your cup size alone.
Calculate → COREBust Size Calculator
Convert a bust measurement into your closest size.
Calculate → COREBand Size Calculator
Isolate and double-check your band size.
Calculate → CONVERSIONBra Size Conversion
Switch between US, UK, EU, AU, and Japanese sizing.
Calculate → CONVERSIONSister Size Calculator
Find an equivalent size when your usual one is out of stock.
Calculate → CONVERSIONBrand Size Converter
See how your size maps to a specific brand's chart.
Calculate → SPECIALTYABTF Calculator
The community 3-measurement method, automated.
Calculate → SPECIALTYSports Bra Calculator
Fit logic built for compression and encapsulation styles.
Calculate → SPECIALTYPlus Size Bra Calculator
A wider band and cup range, with matched guidance.
Calculate → SPECIALTYBreast Volume Calculator
An informational cc/ml estimate — not medical guidance.
Calculate → LIFE STAGEMaternity & Nursing
Built for a body that's actively changing.
Calculate → LIFE STAGEFirst Bra Calculator
A gentler starting point for teens and first-time buyers.
Calculate → LIFE STAGEMen's & MTF Calculator
Sizing built around a different measurement baseline.
Calculate →Popular Guides
Not ready to calculate yet? Start here.
How to Measure Your Bra Size at Home
Everything you need, step by step, with no fitting room required.
7 min readBra Size Chart: US, UK & EU Explained
Why the same letter means something different in every country.
5 min readSigns Your Bra Doesn't Fit
Ten fit signals to check, and what each one actually means.
5 min readSister Sizing Explained
How to find an equivalent size when yours is sold out.
Why Trust IMRango
Every calculator on this site runs on a clearly disclosed method — the standard band-and-bust formula, the community ABTF three-measurement approach, or direct sister-size logic — so you always know what's behind your result, not just a number.
Our sizing data and guides are reviewed on a regular schedule, with a visible last-updated date on every page. Results here are estimates meant to make shopping easier — not a substitute for a professional fitting.
Frequently Asked Questions
How does the Victoria's Secret method work?
Victoria's Secret traditionally uses the +4 method – they add 4 inches to your underbust measurement to get the band size. This results in a looser band and smaller cup letter compared to modern snug fitting.
What is the ABTF method?
The ABTF (A Bra That Fits) method uses 6 measurements (loose, snug, tight underbust; standing, leaning, lying bust) for a more accurate fit, especially for larger busts and different shapes.
What's the difference between US and UK bra sizes?
US and UK bands are the same (e.g., 34 is 34 in both), but cups differ from DD up. US DDD = UK E, US G = UK F, US H = UK FF.
Are sister sizes the same cup volume?
Yes. Sister sizes hold the same cup volume but with different band and cup combinations. For example, 34C → 32D (tighter band) or 36B (looser band).
Does IMRango store my measurements?
No. Everything runs locally in your browser. We do not collect, store, or share any of your personal data or measurements.
Not sure where to start?
Two measurements is all it takes.