PickGlobeBra size calculator and converter
Measure two things for a starting size, or convert a size you already know.
Loading the calculator. Without JavaScript, open the rules below.
- Band is the measurement under the bust; the cup comes from the difference with the bust: 1 inch is A, 2 inches B, and so on.
- UK and US cup letters match up to D, then split (UK DD, E, F; US DD, DDD, G).
- This is a starting point: brands size differently, so check each brand's chart.
How we calculate
The conversions follow Wacoal sizing as published by two retailers, shown under "The conversions we use" with the date we checked. Other brands use different charts.
- Measure. The band is your underbust measurement, shown as the nearest even band from 30 to 46 (UK and US). The cup is the bust minus the underbust: 1 inch is A, 2 is B, 3 is C and so on, using the UK letters in order.
- Convert. Each band and cup is matched by its position in the chart row, so UK 34DD becomes Europe 75E.
- Centimetres. We convert to inches (1 in = 2.54 cm) and round the difference to the nearest inch.
The result is a starting size to try, not a fitting.
The conversions we use
| Item | Rule |
|---|---|
| Band numbers | UK/US 30 to 46 = Europe and Japan 65 to 105 = France 80 to 120 = Australia/NZ 8 to 24, in steps of 2 / 5 / 5 / 2. |
| Cup letters, UK | AA, A, B, C, D, DD, E, F, FF, G, GG |
| Cup letters, US | AA, A, B, C, D, DD, DDD, G, H, I, J |
| Cup letters, Europe and France | AA, A, B, C, D, E, F, G, H, I, J |
| Cup letters, Australia/NZ | AA, A, B, C, D, DD, E, F, FF, G, GG |
| Cup letters, Japan | A, B, C, D, E, F, G, H, I, J, K |
| Measuring | Band: around the ribcage just under the bust, snug not tight. Cup: around the fullest part of the bust. Subtract the band measurement from the bust: 1 inch = A, 2 = B, 3 = C, 4 = D, and so on. |
| Methods differ | David Jones uses the underbust measurement as the band. Belk's chart for Wacoal US sizes adds about 3 inches (29 in underbust = size 32). Other brands differ again, so treat any result as a starting size. |
UK and US cup letters match up to D, then split. Brands size differently, and the sources disagree on some cups: always check the brand's own chart and the size on a bra that fits you.
Checked on 27 October 2026.
Sources and last checked
- Wacoal size conversions and measuring steps, checked 27 October 2026: David Jones: Wacoal size guide (international conversions, how to measure); Belk: Wacoal bra size chart (US sizes, in inches)
A starting size from published retailer charts, not a fitting. Brands size differently and the sources differ on some cups: check the brand's own chart and the size on a bra that fits you. Not medical advice.