Colour Contrast Checker (WCAG)
Check the contrast ratio between text and background colours against WCAG AA and AAA.
Result
How to use
- 1
Pick the text colour and the background colour.
- 2
Read the contrast ratio and the AA / AAA pass or fail badges.
- 3
If it fails, click the suggested colour to fix it.
Questions
What contrast ratio do I need?
WCAG 2.2 level AA needs at least 4.5 : 1 for normal text and 3 : 1 for large text (18 pt, or 14 pt bold) and for icons and form borders. Level AAA needs 7 : 1 and 4.5 : 1.
Is accessibility required for Indian websites?
Government websites must follow the Guidelines for Indian Government Websites (GIGW), which are based on WCAG. The Rights of Persons with Disabilities Act, 2016 also requires accessible information, so meeting AA is a good target for every site.
How is the ratio calculated?
Ratio = (L1 + 0.05) ÷ (L2 + 0.05), where L1 and L2 are the relative luminance of the lighter and darker colours. It ranges from 1 : 1 (same colour) to 21 : 1 (black on white).
About this Contrast Checker tool
Colour Contrast Checker (WCAG) — Check the contrast ratio between text and background colours against WCAG AA and AAA. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Pick the text colour and the background colour.
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Results are estimates to help you plan. They are not financial, tax or medical advice.