What is the validity of contrast and colours tests?

1. Why is Colour contrast important?
2. What is a good color contrast ratio?
3. How do you determine contrast ratio of color?
4. What is color contrast?

Why is Colour contrast important?

Color contrast impacts the readability of your content on the web and in print. It is especially important for users who are low vision or for users who are colorblind. Good color contrast means all users can see your content no matter the device they're using or the lighting of their surroundings.

What is a good color contrast ratio?

Color Contrast Ratios Guidance

Whenever using color in images, ensure that the colors have a contrast ratio of at least 4.5:1. This ensures that the text is still readable to those who may have color blindness.

How do you determine contrast ratio of color?

Calculating a Contrast Ratio

Contrast ratios can range from 1 to 21 (commonly written 1:1 to 21:1). (L1 + 0.05) / (L2 + 0.05), whereby: L1 is the relative luminance of the lighter of the colors, and. L2 is the relative luminance of the darker of the colors.

What is color contrast?

Color contrast is a term used in color theory that describes the difference between different color hues. Tonal contrast — a different type of contrast adjustment — describes the difference between the lightest and darkest tones in the image.