What is the minimum WCAG contrast ratio?

WCAG 2.1 AA requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text. AAA requires at least 7:1 for normal text and 4.5:1 for large text.

What qualifies as large text?

Large text is defined as 18pt (approx 24px) or larger, or 14pt (approx 18.67px) bold or larger.

Does this tool upload my colors?

No. All calculations, relative luminance evaluations, and color modifications happen in your browser using JavaScript. No color data is sent to the server.

WCAG Color Contrast Checker

Evaluate the contrast ratio of text and background colors according to the WCAG 2.1 guidelines. Generate accessible color adjustments instantly.

Text / Foreground Color HEX/RGB/HSL

Background Color HEX/RGB/HSL

Everything runs locally in your browser.

Live Text Preview

Large Heading (18pt Bold / 24pt Regular)

This is a preview of large heading text style.

Normal Text (Under 18pt)

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed vel massa lectus.

Contrast Ratio

18.6:1

WCAG 2.1 Compliance Status

WCAG AA Requirements

Normal Text (4.5:1) PASS

Large Text (3.0:1) PASS

WCAG AAA Requirements

Normal Text (7.0:1) PASS

Large Text (4.5:1) PASS

WCAG 2.1 Guidelines

Easily verify contrast standards to build accessible interfaces that comply with Section 508, ADA, and WCAG AA or AAA guidelines.

Suggestions Engine

Automatically adjust colors incrementally along HSL coordinates to discover closest alternatives that pass the contrast ratio criteria.

Fully Client-Side

Computations are executed locally inside your browser context. No colors, files, or telemetry coordinates are transmitted to our servers.

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