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Utilizing WCAG to Improve Text Readability and Contrast

Sufficient contrast ensures your content is easy to read, especially for users with visual impairments, color vision deficiencies, or simply those viewing your design in less-than-ideal lighting conditions.

Contrast is the difference in brightness between two elements, such as your text and its background. But how do you know when it's enough? Well, the WCAG guidelines define specific contrast ratio thresholds that serve as benchmarks for accessibility:

- 4.5:1 for normal text (under 18pt or 14pt)
- 3:1 for large text (18pt and above or 14pt bold and above).

These ratios are calculated through the Luminance value of the CIE color space... and fortunately for you, tools like Color Schemer can do all the math for you.

Analyzing WCAG with Color Schemer

With Color Schemer, we can take the some of the guess work out of color selection and turn it into a science. Simply go into the "Mix" section of the app, and set a color on each of the columns. Then, you can evaluate the text contrast for different font sizes and weights, and tune the colors with ease.

Screenshot of Color Schemer analyzing and mixing two colors

As an added bonus, you can also mix the two colors through various color spaces, and get a spectrum of the color mixes.

Practical Tips for WCAG-Compliant Design

Think hierarchically. Use stronger contrasts for headlines and weaker ones for secondary text. This creates a natural hierarchy while maintaining accessibility.

Apply to icons and buttons. If your button has white text on a bright red background, it likely lacks sufficient contrast. WCAG could be used to determine how much you need to darken the red to meet the minimum 4.5:1 ratio.

Avoid violent contrast. For example, when designing for dark mode, ensure that your “white” text isn’t pure white (#FFFFFF). A slightly muted white (#EAEAEA) paired with a black background provides better readability while reducing glare and eye strain.

Test across multiple devices and environments. Contrast isn’t static — it can vary based on the device or setting. A design that looks perfect on your fancy monitor might be hard to read on an older laptop or in bright sunlight.

Go beyond color. Add icons or patterns to highlight error messages instead of just using red text. Use underlines or bold styles for clickable links, not just a different color. This ensures that users with color vision deficiencies can still utilize your design.