Contrast Ratio

The contrast ratio indicates the difference in brightness between the foreground and background colors, for example for text and background. It is a key criterion for digital accessibility and is particularly important for people with visual impairments.

According to the WCAG guidelines, the following minimum requirements apply:

• Normal text: At least 4.5:1
• Large text (from 18pt or 14pt bold): At least 3:1
• Enhanced level (AAA): 7:1 for normal text

Too little contrast can make content illegible or cause unnecessary eye strain. The contrast ratio should therefore always be checked - e.g. with tools such as the WCAG Contrast Checker. Even small adjustments can have a big impact on usability.