How can I make slide content easier to understand for people with color-vision differences?

Start by asking whether a person could understand the slide if they could not distinguish the colors you chose. Review charts, status indicators, highlighted text, maps, and legends—not just the main text. Microsoft advises against using color as the only way to communicate information and suggests viewing slides in grayscale to find meaning that depends only on color. [S1]

For each color distinction, add another cue that explains the meaning. Depending on the slide, that could be a direct label, a symbol, a pattern, or a different line style. The cue should make sense on its own, rather than requiring the viewer to remember which color means what.

Look for information that disappears or becomes ambiguous when hues are removed. For example, imagine a two-line chart where blue means “planned” and orange means “actual,” but both lines use the same style and neither is labeled. In grayscale, the lines may be hard to tell apart. Add direct labels such as “Planned” and “Actual” near the lines, or use different line styles as well as color.

Also inspect legends, colored dots, and status words such as “On track” or “Delayed.” If a colored dot is the only sign of status, add the status word or a meaningful symbol. Keep the added cue close to the information it explains where practical, so readers do not have to match distant marks to a legend.

Treat grayscale as a useful review, not a guarantee that every person will perceive every color combination in the same way. Microsoft’s guidance also recommends sufficient contrast between text and its background and identifies PowerPoint’s Accessibility Checker as a way to flag possible contrast issues. [S1] Use the checker as an additional prompt to review; a clean result does not prove every slide is easy for everyone to read.

Check ordinary slide text and text placed over colored shapes or images. If a warning appears, review the affected content and consider whether the text-background contrast is clear. A contrast warning is one part of the review; it does not tell you whether a chart’s categories are understandable without color.

Work through the deck one slide at a time, focusing on places where color carries information. For each one, write down what the color is meant to tell the audience, then check whether a word, symbol, pattern, or line style communicates that meaning too. View the slides in grayscale and see whether you can still interpret the important distinctions. In PowerPoint, you can also review possible contrast issues with its Accessibility Checker. [S1]

For example, if green bars mean “complete” and red bars mean “in progress,” add those words to the bars or beside them rather than relying only on color. Then check that the labels remain readable against their backgrounds.

Use this short record for each slide that relies on color:

• Slide number or title: [slide]
• What the color is meant to communicate: [meaning]
• What non-color cue provides the same information: [label, symbol, pattern, or line style]
• Does the meaning remain clear in grayscale? [yes / needs revision]
• Text or background contrast concern to review: [note]
• Follow-up change: [action]

If you cannot name a non-color cue, that is a useful sign to revise the slide. The grayscale check helps reveal color-dependent meaning, while the additional cue makes the message available through more than color alone. The guidance does not guarantee that any one combination will work for every audience member, so keep labels and other cues clear and review the deck in its presentation context.