Yes, Siteimprove checks for color contrast issues in Accessibility using the following guidelines:
- AA Guideline 1.4.3 Contrast (Minimum): The contrast ratio should be at least 4.5:1 for normal text and 3:1 for large text.
- AAA guideline 1.4.6 Contrast (Enhanced): The contrast ratio should be at least 7:1 for normal text and 4.5:1 for large text.
Insufficient contrast between text and its background can create difficulty for visually impaired or color-blind users. In general, sufficient contrast is good practice as insufficient contrast can affect all users leading to important text being overlooked.
Note: Contrast measurements are not relevant where content is hidden. However, the contrast ratio should be sufficient for hidden content which becomes visible when receiving focus.