Step 1:

Paste or enter colors (each on its own line). HEX colors are easiest, but rgb() values are also accepted. Submit our default list to see what happens. Click the button and Go!

Step 2: Review colors!

Criteria

This tool shows three different ratio targets and how your color performs with each — white, black, or other colors in your palette:

  • WCAG Level AAA: a contrast ratio equal or greater than 7.0. For large-scale text, a ratio equal or greater than 4.5.
  • WCAG Level AA: a contrast ratio equal or greater than 4.5. For large-scale text, a ratio equal or greater than 3.0.
  • Text that is considered “Large-scale” is 18 points (24px) or larger or 14 points (19px) and bold or larger.

For more details about success criteria, see the WCAG 2.1 minimum contrast ratios page.

Modify with HSL

Why HSL? By modifying primarily the saturation and/or lightness, the original intention of the color is intact. To modify the Hue would be to start to modify the color from a blue to a blue-green, or from a red to an orange. Of course, modify the Hue as you wish as well, but our intention is to show how small movements to the saturation and lightness can increase accessibility while retaining the intention of the brand color. More about how HSL works.

Edge values

Be careful with EDGE values — the color passes validation, but is within 0.5. It may still present a legibility issue even though it gets a passing grade.

Most legible Pair

From the given list of colors, which color combination is the most legible? This does not mean that the color pair will pass minimum requirements, but it has the best chance of passing.

Custom: Use the text input to change the color pairing.

Check your hover text color vs. your body text color

If links are not underlined, there must be 3:1 contrast between link text and body text and also an additional change (e.g., underlining) on mouse hover and keyboard focus. Use the tool to compare your link color against your body text color to see how they pair in the Most Legible column.