The term “color contrast” describes the differences in brightness and color between elements in a photograph or, more importantly for our purposes, text and a colored backgrounds.
Because color contrast is essential to the readability of documents, slide presentations, and websites, it is a key component of universal design. Some of your readers (an estimated 4% of the population) will have low vision. Others (approximately 8.5% of the population) will have some form of color blindness (also known as color vision deficiency), meaning they may have difficulty distinguishing red from green, or yellow from blue. Use the following techniques to help make your publications accessible to everyone:
- Choose a color scheme that provides high contrast between the text and the background. If you have a dark background, the text should be light, and vice versa. (Black and white provide maximum contrast.)
- Use larger text and simple (not ornate) fonts.
- Use a contrast checking tool (online or downloadable) to determine whether your color selections are legible by a wide range of users. We recommend the Colour Contrast Analyser by the Paciello Group.
- If you are building a webpage, check it with a color blindness simulation tool. Avoid the following color combinations as they are difficult to read, especially for individuals with color vision deficiency:
- Green and red (or related colors)
- Blue and yellow (or related colors)
- Don’t rely on color as the sole means of conveying information. For example, don’t use color as your only method of indicating heading levels.
- Text can be difficult to read on photographic or gradient backgrounds. Set text against a solid background when possible.