Colour contrast checker & converter
Pick a text and a background colour to see the WCAG contrast ratio and whether it passes AA or AAA. Colours are converted between HEX, RGB and HSL.
The quick brown fox jumps over the lazy dog
Voluntary support · Thank-you gift: our checklist PDF · Secure checkout via Digistore24 (Apple Pay, Google Pay, PayPal, card)
🔒 Runs entirely in your browser – nothing you enter is uploaded or stored.
How to use it
- Choose the text colour and the background colour (picker or HEX).
- Read the contrast ratio and the AA/AAA results.
- Copy the colour in HEX, RGB or HSL format.
Last checked: October 2026. Found a mistake? Use the form below – we fix confirmed errors and update the date.
Frequently asked questions
What contrast does WCAG require?
Level AA: at least 4.5:1 for normal text and 3:1 for large text and UI components. Level AAA: 7:1 for normal and 4.5:1 for large text.
How is the ratio calculated?
(L1 + 0.05) ÷ (L2 + 0.05), where L1 and L2 are the relative luminances of the lighter and darker colour, as defined in WCAG 2.x.
Why does contrast matter?
Good contrast makes text readable for people with low vision, colour-vision deficiencies or in bright sunlight – and it is required for accessibility compliance (e.g. EN 301 549, the European Accessibility Act).