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    Free WCAG Color Contrast Checker

    Report a problem

    Test contrast ratio based on WCAG standards

    Sample Text

    The quick brown fox jumps over the lazy dog

    21.00:1
    Contrast Ratio
    AA Large Text (3:1)Pass
    AA Normal Text (4.5:1)Pass
    AAA Large Text (4.5:1)Pass
    AAA Normal Text (7:1)Pass
    Client-Side Processing
    Instant Results
    No Data Storage

    What is Color Contrast Checker?

    Great color palettes can still fail if text is hard to read. Designers often discover contrast issues late in the process, after assets have shipped across screens and platforms.

    Color Contrast Checker makes accessibility a first-class part of the workflow. It gives an immediate ratio and pass/fail status so you can adjust colors while designing.

    Use it for UI components, marketing graphics, and print proofs where readability and compliance matter.

    Beautiful palettes can be unreadable in practice

    Color choices that look good in a mockup can fail contrast requirements in production.

    Designers often rely on intuition without measuring accessibility ratios.

    Brand colors can be too light for text, forcing awkward compromises late in the process.

    Different screens and brightness settings can exaggerate contrast issues.

    Measure contrast early and adjust with confidence

    Check contrast ratios for any text and background pair and verify WCAG AA/AAA status.

    Use the result to adjust colors, text size, or weight to meet accessibility goals.

    Limitations: contrast ratios are one part of accessibility and do not replace full audits.

    How to Use Color Contrast Checker

    1. 1Set text color - Enter or pick the foreground color.
    2. 2Set background color - Enter or pick the background color.
    3. 3Review contrast ratio - Check the numeric ratio result.
    4. 4Check AA/AAA status - Confirm pass or fail for normal text.
    5. 5Test large text - See if larger text passes when normal does not.
    6. 6Adjust colors - Modify values until the target passes.
    7. 7Validate in context - Check the result on real UI elements.

    Key Features

    • Real-time contrast calculation
    • WCAG 2.1 AA/AAA compliance check
    • Color picker interface
    • Hex, RGB, and HSL support
    • Visual preview
    • Pass/fail indicators

    Benefits

    • Ensure website accessibility
    • Meet legal accessibility requirements
    • Improve readability for all users
    • Design inclusive interfaces
    • Avoid accessibility lawsuits

    Use cases

    UI components

    Validate buttons, labels, and input fields.

    Marketing graphics

    Ensure headlines are readable on banners.

    Brand systems

    Define accessible color pairs for guidelines.

    Social visuals

    Improve readability on mobile feeds.

    Product design reviews

    Catch contrast issues before handoff.

    Dark mode themes

    Validate inverted palettes and surface colors.

    Print prep

    Check contrast in proofs and comps.

    Accessibility audits

    Document contrast ratios for compliance.

    Tips and common mistakes

    Tips

    • Check contrast early in the design process.
    • Use larger text or bold weight when contrast is low.
    • Test on multiple devices and brightness levels.
    • Keep a set of approved accessible color pairs.
    • Use neutral backgrounds for readability when needed.
    • Document contrast ratios in your design system.
    • Avoid relying solely on color to convey meaning.
    • Pair contrast checks with real UI screenshots.

    Common mistakes

    • Assuming brand colors always pass accessibility.
    • Ignoring contrast when using gradients or images.
    • Checking only one breakpoint or device.
    • Using light text on light backgrounds for style.
    • Skipping contrast checks for small text.
    • Assuming contrast alone covers accessibility needs.
    • Failing to test hover and disabled states.
    • Overlooking contrast in charts and data visualizations.

    Educational notes

    • WCAG AA is the common minimum; AAA is stricter.
    • Contrast ratios are based on luminance, not hue.
    • Large text has lower contrast requirements.
    • Gradients can lower contrast in certain areas.
    • Brand consistency should not override readability.
    • Cross-platform display differences can affect contrast perception.
    • Accessibility is more than contrast; include focus states and semantics.
    • Exported assets should preserve contrast in raster formats.
    • Use consistent color naming to avoid accidental swaps.

    Frequently Asked Questions

    Do gradients pass contrast checks?

    You need to test the lightest and darkest areas where text sits.

    Is AA enough for compliance?

    Often yes, but requirements vary by region and product.

    Does font weight affect contrast?

    Weight does not change the ratio, but larger or bolder text has different thresholds.

    Can I use this for charts?

    Yes, but also avoid relying on color alone for data meaning.

    Why does a color pair pass in one tool and fail in another?

    Different tools may round or interpret luminance slightly differently.

    Does contrast guarantee readability?

    It helps, but typography and spacing also matter.

    How do I fix a failing pair?

    Adjust brightness, change the background, or increase text size.

    Do icons need contrast checks?

    Yes, especially if they convey important information.

    Is this enough for full accessibility?

    No. It is a single check within a broader audit.

    Does the tool store my colors?

    No. All calculations are local.

    Can I use this for print?

    Yes, but print contrast can differ; check proofs.

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