Medical ImagingGenerated accuracy model review: 2026-05-06

Window / Level 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

**Min HU** = Level - (Width / 2) **Max HU** = Level + (Width / 2) Any pixel with HU < Min is black. Any pixel with HU > Max is white. Pixels in between are shades of gray.

Test cases

Default input regression check

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

Inputs

Window Width (WW): 400 HU
Window Level (WL): 40 HU

Expected outputs

Visible HU Range: -160 to 240 HU
Black Point (< Min): -160 HU
White Point (> Max): 240 HU

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 math assumes a simple centered window calculation and does not model viewer-specific rendering nuances.
Display appearance still depends on monitor calibration, reconstruction, and the actual image data.
Window settings help visualization, but they do not replace careful review of the original acquisition and full imaging context.

Unit handling

Window Width (WW) accepts values in HU.
Window Level (WL) accepts values in HU.
Black Point (< Min) is displayed in HU.
White Point (> Max) is displayed in HU.

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 window-level-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Window / Level.

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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