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Math & AlgebraGenerated accuracy model review: 2026-05-06
Circle 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
- **Diameter** = 2 × r **Circumference** = 2 × π × r **Area** = π × r²
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Radius: 5
Expected outputs
- Area: 78.54
- Circumference: 31.42
- Diameter: 10
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
- The radius is entered in a linear unit, and outputs use the matching linear or square unit.
- Radius is treated as a non-negative length.
- Pi is approximated with JavaScript's built-in Math.PI constant.
Unit handling
- Radius accepts numeric values.
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 circle-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Circle Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.