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Everyday LifeGenerated accuracy model review: 2026-05-06
Bra Size Calculator accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- 1. **Band Size:** Usually the Underbust measurement rounded to the nearest even number (sometimes +0, +2, or +4 inches depending on the sizing system - this calculator uses the modern +0/rounding method). 2. **Cup Size:** The difference between Bust and Band. (1 inch = A, 2 inches = B, 3 inches = C, etc.).
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Snug Underbust (Band): 32 in
- Loose Overbust (Bust): 36 in
Expected outputs
- Estimated Size: 32D
- Sister Sizes: 30DD/E, 34C
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- Measurements are taken in inches using a soft tape measure.
- The calculator follows a modern +0 style sizing method.
- Brand, style, and shape differences can still change the final fit.
Unit handling
- Snug Underbust (Band) accepts values in in.
- Loose Overbust (Bust) accepts values in in.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current bra-size-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Bra Size Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.