TWO COLORS. FOUR THRESHOLDS.
Put your pair
to the test.
Check a text and background color against WCAG 2 text-contrast thresholds. Enter two opaque sRGB hex values, check the pair, then adjust manually.
01 / YOUR PAIR
Set the colors
Enter two colors to begin.
LOCAL BY DESIGN
No uploads. No accounts. No saved history.
02 / CONTRAST RATIO
�:1
Awaiting your pair
Your checked colors appear here.
Make every word count.
Good design gives ideas room to be read. This is regular sample text.
A bold idea, clearly expressed.
Large text means at least 18 pt regular or 14 pt bold. Verify your actual font size and weight separately.
Ratios display to three decimal places; decisions use the unrounded ratio. A displayed value may round to a threshold while remaining below it.
03 / KEEP THE EVIDENCE
Plain-text report
UTF-8 text, saved only when you click Download. Browser settings may prompt, open or block saving; select and copy the report as a fallback.
One pair. A limited check.
Opaque solid sRGB text/background pairs only. The sample is illustrative; contrast alone does not establish readability or accessibility conformance. No alpha, gradients, photographs, font inspection, APCA or whole-page certification.
Inputs and results stay in volatile tab memory. Reset or reload discards app-held data. No storage, telemetry, uploads or external processing.
Method: W3C contrast minimum and contrast enhanced. These links are references, not runtime dependencies.
Desk notes / FAQ
How do I check a pair and interpret the four results?
Enter one foreground and one background as #RGB or #RRGGBB, then choose Check contrast. AA normal text needs 4.5:1, AA large text 3:1, AAA normal text 7:1 and AAA large text 4.5:1. Large text means at least 18 pt regular or 14 pt bold; verify your actual font size and weight separately.
Are my colors stored or uploaded? Do I need permissions?
No. Inputs and results stay in volatile tab memory, with no uploads, accounts, telemetry or persistent storage. No device permissions are requested. Only clicking Download requests a local text file; browser settings control saving.
Why is the download disabled after I edit or swap colors?
Any edit, Swap or example replacement invalidates the previous result. Choose Check contrast again to create a current report. Invalid submissions preserve your entered strings. Reset or reload discards app-held inputs and results; there is no saved history to recover.
Can this certify a page or check transparent colors?
No. This checks one opaque solid sRGB text/background pair only. Alpha, CSS expressions, named colors, gradients and photographs are rejected or outside scope. The illustrative sample cannot inspect actual fonts or establish readability or accessibility conformance. Decisions use unrounded ratios even when the three-decimal display rounds to a threshold.