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Free Online Color Contrast Checker

Calculate WCAG sRGB relative-luminance contrast and AA/AAA text thresholds for two opaque colors.

Your input stays on this device. Processing is bounded; regex runs in a worker with a two-second timeout.

Result



How to use Color Contrast Checker
Calculate WCAG sRGB relative-luminance contrast and AA/AAA text thresholds for two opaque colors.
  1. Set Color.
  2. Set Other Color.
  3. Run the tool, review the result and its stated limitations, then copy or download if needed.
Example & practical use
Calculate WCAG sRGB relative-luminance contrast and AA/AAA text thresholds for two opaque colors. The example below demonstrates Color; Other Color.
Example input:
{
  "color": "#000000",
  "otherColor": "#ffffff"
}
Expected result (relevant fields):
{
  "ratio": 21,
  "aaNormal": true,
  "aaaNormal": true
}
Features & result limitations
Calculate WCAG sRGB relative-luminance contrast and AA/AAA text thresholds for two opaque colors.
Frequently asked questions
What inputs does Color Contrast Checker accept?
Color; Other Color
How should I interpret the Color Contrast Checker result?
Calculate WCAG sRGB relative-luminance contrast and AA/AAA text thresholds for two opaque colors.
Where does Color Contrast Checker process my data?
Inputs are processed locally in your browser. Submitted text is not sent to external services. A successful-run event increments an aggregate tool counter without your input.