Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Unit Converters
Bra Size Conversion Calculator (US, UK, EU, AU)
EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
Band in inches (US/UK) and cup letter. EU bands are centimeters rounded to 5 (34 → 75). Cup letters drift after D: UK DD vs US DD/E is a forum war. Sister sizes (34C / 32D) share cup volume, not this converter’s job.
US / UK band
Labels
34B
Sister sizes share volume.
- UK
- 34B
- EU
- 85B
- AU
- 12B
Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
US band (in)
The “US band (in)” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
Band in inches (US/UK) and cup letter. EU bands are centimeters rounded to 5 (34 → 75). Cup letters drift after D: UK DD vs US DD/E is a forum war. Sister sizes (34C / 32D) share cup volume, not this converter’s job. EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D. Example: 34B US → 34B UK, ~75B EU, ~12B AU.
EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
Example: 34B US → 34B UK, ~75B EU, ~12B AU.
When to use this Bra Size
Common use cases
- Band in inches (US/UK) and cup letter. EU bands are centimeters rounded to 5 (34 → 75). Cup letters drift after D: UK DD vs US DD/E is a forum war. Sister sizes (34C / 32D) share cup volume, not this converter’s job.
- Sanity-check with this case: 34B US → 34B UK, ~75B EU, ~12B AU.
- The relationship is: EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
Localized examples
- Unit Converters: the example on this page uses the same formula as the widget.
What you get
- Fields: US band (in)
- EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
- Example on the page: 34B US → 34B UK, ~75B EU, ~12B AU.
How to Convert Bra Size Step-by-Step
- 1Enter US band (in). Use the values you have, not a catalog average, unless that is all you know.
- 2EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
- 3Worked case: 34B US → 34B UK, ~75B EU, ~12B AU.
- 4Check which dictionary the other person is using — US or UK, decimal or 1,024 — then trust the number.
Governing formula
EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.
34B US → 34B UK, ~75B EU, ~12B AU.
Example: set US band (in) = 34, then read the result.
Variable definitions
- value
US band (in)
The “US band (in)” field. Default 34; typical range 28–46.
- The conversion (EU band ≈ round(band_in × 2.54 / 5) × 5. Cup letter copied with a warning past D.) does not pick US vs UK gallons, SI vs binary megabytes, or Mach at altitude for you. Read the footnote on the page.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
Go down a band, up a cup (34C → 32D) for similar volume. Try both.
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Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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