Color Contrast Checker: Test Text Readability
Calculate contrast between foreground and background colors. Interpret the ratio alongside text size and the relevant WCAG criterion.
This guide and page information are in English. Some controls inside the interactive tool currently appear in Turkish.
This tool processes its main input in your browser and does not send it to an external API. Fonts and interface assets may load from external providers.
Color Contrast Checker: Test Text Readability
The contrast checker reports a ratio between two colors to help evaluate whether interface text stands apart from its background.
A ratio does not measure all of accessibility. Text size, weight, visual states and the actual background matter; test the colors shown by the finished component.
How to use it
- Enter foreground and background colors.
- Review the contrast ratio and the displayed WCAG threshold.
- Check the actual component in different states and with additional accessibility methods.
Example
Input: #000000 text on #FFFFFF background
Output: A contrast ratio of 21:1
Who is it for?
- UI designers
- Accessibility reviewers
- Frontend developers
Privacy and limitations
The contrast calculation runs in this browser and the color values are not sent to an API.
Frequently asked questions
What does 21:1 mean?
It is the maximum standard ratio for extreme luminance values such as black and white; it does not prove that a complete component meets every requirement.
Does meeting WCAG AA make every user able to read it?
No. Thresholds are useful checks, while font size, environment and different visual perception also affect usability.
What if the background is an image?
Check the actual area behind the text, including the lowest-contrast region. Variable imagery may require multiple checks.
Does the ratio update when I change a color?
Yes. Update the color fields and review the recalculated value in the interface.