Color Contrast Checker

Color Contrast Checker formula or transformation

For Color Contrast Checker, relative luminance is calculated from linearized sRGB channels; contrast ratio = (lighter luminance + 0.05) ÷ (darker luminance + 0.05).

Worked Color Contrast Checker values

Worked values: Text color = #111827; Background color = #ffffff Color Contrast Checker expected result: The result is a output produced only from the supplied sample fields by the transformation described above.

Color Contrast Checker accessibility context

For Color Contrast Checker, the report compares the computed ratio with WCAG 2.2 thresholds: 4.5:1 for normal text and 3:1 for large text at level AA, plus the displayed enhanced thresholds. For Color Contrast Checker, passing contrast alone does not establish complete accessibility.

Color Contrast Checker limits and verification

For Color Contrast Checker, results use browser JavaScript number, string, and color parsing. For Color Contrast Checker, validate generated CSS in the target browser and do not treat a palette or format conversion as a design-system or accessibility approval. To verify Color Contrast Checker, reproduce its worked example and compare the displayed or downloaded output with the stated expected result. When Color Contrast Checker returns a file, open the download and inspect every affected page or image.

Color Contrast Checker browser processing

Color Contrast Checker runs the contrast checker operation in the current browser session. Color Contrast Checker reads and processes the supplied values in the current browser and does not submit them to an application endpoint. Browser extensions, device security and any manual sharing or download from Color Contrast Checker remain outside the tool’s control.

Accessibility source for Color Contrast Checker

W3C WCAG 2.2

Frequently asked questions

Color Contrast Checker accepts Text color and Background color and produces Output. Supported input: Color Contrast Checker accepts Plain text or form values shown by this tool.

Color Contrast Checker runs the contrast checker operation in the current browser session.

For Color Contrast Checker, no explicit text-length, file-size or numeric-range cap is enforced by this operation code..

Color Contrast Checker precision: the operation returns strings or counts directly; no additional decimal rounding rule is applied unless the result panel states one.

To verify Color Contrast Checker, reproduce its worked example and compare the displayed or downloaded output with the stated expected result. When Color Contrast Checker returns a file, open the download and inspect every affected page or image.