Health & FitnessGenerated accuracy model review: 2026-05-06

BMI 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

The formula for BMI is: **Metric:** Weight (kg) / [Height (m)]² **Imperial:** 703 × Weight (lbs) / [Height (in)]² The resulting number maps to standard categories defined by the WHO and CDC.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

Units: Imperial (ft/lbs)
Height (Feet): 5
Height (Inches): 10
Height (cm): 178
Weight (lbs): 160
Weight (kg): 70

Expected outputs

BMI Score: 23
Category: Normal Weight

Known limitations

BMI does not distinguish between muscle mass and fat mass. It implies that a high weight-to-height ratio is due to fat, which isn't always true for athletes.

Assumptions

BMI assumes weight relative to height is a useful screening proxy for health risk in the general adult population.
The result uses standard adult BMI cutoffs rather than athlete-specific, child-specific, or pregnancy-specific guidance.
BMI does not separate fat mass from muscle mass or show where weight is carried.

Unit handling

Units accepts one of the configured options.
Height (Feet) accepts numeric values.
Height (Inches) accepts numeric values.
Height (cm) accepts numeric values.
Weight (lbs) accepts numeric values.
Weight (kg) 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 bmi-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for BMI Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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