About the Color Contrast Checker (WCAG Compliance)
Sufficient contrast between text and its background is one of the most fundamental web accessibility requirements — without it, users with low vision or color blindness (and honestly, anyone viewing a screen in bright sunlight) can struggle to read your content at all. This checker calculates the exact contrast ratio between any two colors and tells you whether it meets WCAG accessibility standards.
This tool is useful for designers and developers verifying their color choices are accessible before shipping a design, accessibility auditors reviewing an existing website's compliance, and anyone building a design system who wants to establish text/background color pairs that reliably meet accessibility guidelines from the start.
To use it, enter or pick a text color and a background color. The tool calculates the exact contrast ratio (a number from 1:1 for no contrast to 21:1 for pure black on white) and reports whether it passes WCAG AA and AAA standards for both normal text and large text (which have different required minimum ratios, since larger text is inherently easier to read at lower contrast). A live preview shows sample text rendered in your chosen colors so you can visually confirm readability alongside the numeric result.
For example, dark gray text (#333333) on a white background produces a contrast ratio of about 12.6:1, comfortably passing both AA and AAA standards for all text sizes, while a popular but risky combination like light gray text (#999999) on white only achieves roughly 2.8:1 — failing even the more lenient AA standard for normal-sized text, meaning that combination should be avoided or reserved only for large, bold headings where the lower threshold applies.
A common mistake is judging contrast purely by eye, which is notoriously unreliable — colors that look "different enough" on a good monitor in ideal lighting can fail formal contrast requirements and become genuinely difficult to read for many users in different conditions, making an objective numeric check essential rather than optional. Another frequent issue is checking contrast only for a design's primary body text while overlooking secondary elements like placeholder text, disabled button labels, or captions, which often use lower-contrast gray tones that can fail accessibility standards even when the main content passes.
Tip: WCAG AA (4.5:1 for normal text, 3:1 for large text) is the widely accepted minimum standard for most websites and is a legal requirement in many jurisdictions; aim for AAA (7:1 for normal text) whenever practical for content where readability is especially critical, like body copy in long-form articles.