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Check WCAG contrast ratio between text and background colors for accessibility compliance.
Find the closest accessible text color (black, white, or adjusted hue) meeting WCAG AA.
Simulate how colors appear to Deuteranopia, Protanopia, Tritanopia, and Achromatopsia vision.
Visual color picker showing real-time HEX, RGB, HSL, HSV, and CMYK formats.
Calculate Euclidean and CIE76 Delta E perceptual color distance between two colors.
Validate 3, 6, and 8-digit HEX color codes and normalize formatting.
This WCAG accessibility checker runs a comprehensive compliance test on your color pairings, covering AA and AAA thresholds for normal text, large text, and UI components in a single pass. It's built for accessibility auditors and developers who need a full compliance breakdown rather than a single contrast number, and for design system teams validating every text and component color combination against WCAG 2.1 before release. Enter your color pairs and the tool checks each one against every relevant success criterion, clearly flagging which pass and which fail, along with the exact ratio calculated for each. Everything runs client-side in your browser, meaning color combinations tied to unreleased products or internal design systems are never transmitted anywhere. The success criteria and thresholds used match the official WCAG 2.1 specification exactly, so the results are audit-grade and consistent with what a formal accessibility review would find. Enter your colors below to run the full compliance check.
This tool covers the full WCAG 2.1 checklist including UI component and non-text contrast (criterion 1.4.11), not just text contrast, giving a more complete compliance picture.
WCAG 2.1's non-text contrast criterion requires at least a 3:1 ratio for UI components like buttons, form borders, and icons against their surroundings.
Yes, WCAG 2.1 Level AA is the most commonly referenced standard in accessibility laws and regulations such as the ADA and Section 508 in the US, and EN 301 549 in the EU.
AAA is a stricter, optional standard; most organizations aim for AA compliance since AAA can be difficult to achieve across an entire design system without limiting color choices.
No, color contrast is only one part of accessibility; a full audit also needs to cover keyboard navigation, screen reader support, semantic markup, and more.
Yes, the tool is designed to let you test several text and UI color pairs in the same session for a broader compliance review.
WCAG Contrast Ratios Explained: AA vs AAA
What the WCAG contrast ratio numbers mean, how 4.5:1 and 7:1 were chosen, when large text qualifies for 3:1, and how to decide whether you need AA or AAA.
Why You Shouldn't Rely on Color Alone
WCAG 1.4.1 Use of Color is Level A. Exactly what color alone accessibility forbids, the four places designs break it, and non-color indicators that work.
The Complete Guide to Accessible Color and Contrast
A complete guide to accessible color: WCAG 2.1 contrast ratios, how contrast is calculated, color blindness types, and practical fixes for failing palettes.