Find your starting size
Two measurements, about two minutes, and a size you can actually go and try on - plus the arithmetic we used to get there.
- No account
- Nothing stored
- Method shown
Not sure where to put the tape? Read the measuring guide first.
A starting size - then check the fit
Before you measure
Two numbers, taken properly
Almost every inaccurate result comes from the tape, not the maths. These two steps take about ninety seconds.
Snug underbust
Tape directly under the bust, level all the way round, pulled firm. Breathe normally and read at the end of a normal exhale. This gives your band.
Full bust
Tape across the fullest point, resting rather than pulled, level front and back. Do not compress. The difference between the two gives your cup.
Fit troubleshooting
Something not sitting right?
Most fit problems have one cause and one fix. Start with the symptom.
Band rides up
Almost always a band that is too loose. Go down a band, up a cup.
Diagnose →Cup gapes
Usually a cup too large - or a style that does not match your shape.
Diagnose →Tissue spills over
The cup is too small, whatever the letter sounds like.
Diagnose →Straps slip
Three causes: long straps, a loose band, or shoulder slope.
Diagnose →Wire digs in
The wire is sitting on tissue instead of on your ribcage.
Diagnose →Between sizes
Sister sizes keep the cup volume and change the band.
Diagnose →Buying from overseas? AU · UK · US · EU
Reference
The Australian size chart
The same table the calculator uses. Real HTML, readable on a phone, never a picture of a chart.
Scroll the table sideways on a narrow screen.
| Snug underbust | AU / NZ band | UK band | US band | EU band |
|---|---|---|---|---|
| 63–67 cm | 8 | 30 | 30 | 65 |
| 68–72 cm | 10 | 32 | 32 | 70 |
| 73–77 cm | 12 | 34 | 34 | 75 |
| 78–82 cm | 14 | 36 | 36 | 80 |
| 83–87 cm | 16 | 38 | 38 | 85 |
| 88–92 cm | 18 | 40 | 40 | 90 |
| 93–97 cm | 20 | 42 | 42 | 95 |
| 98–102 cm | 22 | 44 | 44 | 100 |
| 103–107 cm | 24 | 46 | 46 | 105 |
| 108–112 cm | 26 | 48 | 48 | 110 |
| 113–117 cm | 28 | 50 | 50 | 115 |
| 118–122 cm | 30 | 52 | 52 | 120 |
| 123–127 cm | 32 | 54 | 54 | 125 |
Why trust this
The method is published
Every threshold and conversion in this calculator lives in a versioned configuration file. The version is printed with your result. When a chart changes, the version changes and we record what changed and why.
Your measurements are calculated in your browser. They are not sent to us, not written to a database, not put in a URL and not passed to any analytics or advertising service.
What this is not
- Not a guarantee of fit - brands vary too much.
- Not medical advice, and not a comment on breast health.
- Not a shop, and not an email list.
- Not a judgement about any body.