Alt text for charts and infographics

A product photo and a bar chart are both "images" as far as your CMS is concerned, but they ask completely different things of alt text. Describe a chart the way you'd describe a photo — colors, shapes, positions — and you'll hand someone a wall of furniture with no idea what it means.

The photo habit that doesn't transfer

For a photo, alt text describes what's visually there: a person, a product, a setting. For a chart, the visual details — bar colors, axis lines, legend placement — are almost never the point. The point is what the data says. Someone listening to your chart's alt text wants the conclusion, not a tour of the chart's design.

The second version tells you exactly what mattered enough to put in a chart in the first place. The first tells you it was blue.

When one sentence isn't enough

A simple two-bar comparison fits in a normal alt text sentence. A dense infographic with several sections doesn't, and forcing it into 125 characters loses real information. For those, lead with the single biggest takeaway in the alt text itself, then use a longer description field if your platform or CMS offers one — many do, specifically for this purpose. If yours doesn't, put the fuller breakdown in the surrounding body copy or caption, and keep the alt text focused on the one thing a listener most needs to walk away with.

A quick way to write it

Before describing anything visual, ask what the chart is arguing. A chart exists to make a point — growth, decline, a comparison, a share of total. State that point first, add the specific numbers that back it up, and stop. You'll rarely need to mention color, chart type, or layout at all; the reader doesn't need the chart's design, they need its conclusion.