Sufficient contrast between text and its background is one of the most impactful and easiest-to-fix accessibility issues, affecting readability for people with low vision and anyone reading on a low-quality screen or in bright light.
This tool calculates the WCAG contrast ratio between your chosen colors and reports whether the combination passes the AA and AAA thresholds for normal text.
Because everything runs locally in your browser, results appear instantly and nothing you type or upload is ever sent to a server.
Bookmark this page if you expect to use this tool regularly — it loads fast and behaves the same way every time, with no account needed.
This kind of task shows up constantly in everyday writing, coding, design, and admin work, which is exactly why a dedicated, focused tool saves so much back-and-forth.
A tool that does one job well, without a cluttered interface or unrelated features competing for attention, tends to be faster to use than a heavier all-in-one app.
If you find yourself needing this conversion or calculation often, keeping this page open in a tab is usually faster than digging through a bigger software suite's menus.
Because there's no sign-up or installation step, you can jump straight from search result to working tool in a couple of seconds.
Getting a reliable, focused result quickly matters more for a task like this than having extra options you'll rarely use.
Because the calculation or conversion happens instantly as you type, you can experiment freely and see how changing one value affects the result.
This page works the same way on a phone, tablet, or desktop browser, so switching devices doesn't mean relearning a different interface.
Frequently asked questions
What ratio do I need to pass AA?
At least 4.5:1 for normal text, or 3:1 for large text (roughly 18pt and above, or 14pt bold).
What's the difference between AA and AAA?
AAA is a stricter standard requiring at least 7:1 contrast for normal text, intended for enhanced accessibility beyond the minimum AA requirement.