Providing Alt Text for Graphs

Have you considered how someone with low vision might interact with a graph you present in your course? Just like other images, screenshots or pictures of graphs need to have alt text that describes the chart and provides “at a glance” information about its key message. An example of good alt text for a graph might be, “A line chart of average student grades over time, where grades improve gradually over the semester.”

Following this example, you might apply this template to create good alt text for a chart or graph: [Chart type] of [data description], where [insert reason for including chart / takeaway].

Note: Key to making a graph or chart fully accessible is ensuring that someone who cannot perceive the chart visually has access to all the instructional content that the graph provides to sighted learners. In addition to alt text, this may require providing the full data table used to generate the chart, and/or a longer description linked near the chart that more fully describes its message.

For more information about creating alt text for graphs, visit Nightingale: Journal of the Data Visualization Society.