Formula and calculation method
Illustrative UK band = nearest even inch to underbust. Cup step = nearest inch difference between bust and band.
A fitting starting point only. Brand fit, measurement methods and country cup labels differ.
How to use bra size calculator
- Set Underbust (cm). The example below uses 80.
- Set Bust (cm). The example below uses 95.
- Select Calculate to update the result. Reset restores the illustrated inputs. Copy, print or download your own result if you need a record.
Worked example
Example inputs
- Underbust (cm)
- 80
- Bust (cm)
- 95
- Approximate band (inches)
- 32
- Illustrative UK cup
- DD
Factors affecting your result
A fitting starting point only. Brand fit, measurement methods and country cup labels differ.
Changing underbust (cm) changes the scenario being evaluated. Adjust one input at a time when comparing results, keep a copy of the assumptions, and compare values using the same unit and period. A precise arithmetic result does not make an uncertain assumption precise.
Frequently asked questions
How does the bra size calculator work?
Illustrative UK band = nearest even inch to underbust. Cup step = nearest inch difference between bust and band.
What inputs does Bra Size Calculator need?
Enter underbust (cm), bust (cm). Choose values that correspond to the same situation and measurement convention.
How should I interpret the bra size calculator result?
A fitting starting point only. Brand fit, measurement methods and country cup labels differ.
Are my bra size calculator inputs uploaded?
No. The calculation runs in this browser. Favorites, recent tool names, theme and formatting preferences may be saved locally, but calculation inputs are not sent to a calculation server or stored by this website. Shared links do not include entered values.
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