- 1Choose file
- 2Adjust
- 3Download
WCAG Color Contrast Checker online, free
Test foreground and background color combinations against WCAG 2.1 AA and AAA standards for accessible web and UI design.
- Runs in your browser — no upload
- Free, no sign-up, no watermark
- TXT
- JSON
How to use WCAG Color Contrast Checker · WCAG Color Contrast Checker — frequently asked questions
How to use WCAG Color Contrast Checker
- 1
Add your TXT and JSON file
Drop a file on the page, paste it, or click Select Files. Nothing is uploaded — it opens straight in your browser.
- 2
Fine-tune the settings
The defaults already suit most files; change them only if you need to.
- 3
Run WCAG Color Contrast Checker
Press the start button. Processing happens on your device, usually in seconds.
- 4
Download the result
Save the finished file, or continue with another tool without downloading in between.
What WCAG Color Contrast Checker can do
- Private by design — files are processed in your browser and never uploaded
- Free with no sign-up, no watermark and no daily limit
WCAG Color Contrast Checker — frequently asked questions
Is WCAG Color Contrast Checker really free?
Yes. WCAG Color Contrast Checker is completely free on Sada Files — no ads, no premium tier, and no usage limits. Every tool and feature is accessible to everyone.
Do I need to create an account or sign in?
No. Sada Files requires no accounts and has no sign-up forms. Simply adjust colors, test contrast ratios, and check WCAG compliance instantly in your browser.
Are my color schemes or files uploaded to any server?
No. The contrast checker runs entirely on your device inside your web browser. No color codes, text inputs, or files leave your machine.
What WCAG standards are tested?
The tool calculates relative luminance and color contrast according to WCAG 2.1 guidelines, reporting compliance for AA and AAA levels across normal text (16px), large text (18pt / 24px or bold 14pt / 18.66px), and graphical user interface components (3:1 ratio).
Does the contrast checker work offline on mobile devices?
Yes. The web application runs offline in modern browsers, and the free native Sada Files app for Android, iOS, Windows, macOS, and Linux performs contrast checks without internet access.
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