Not all graphs require a long description. More simple graphs and charts can be easily described in 3-4 sentences and can go directly into the Alt-text. When they do need a long description it is important to focus on the facts and data more than any visual elements.

As with maps, ask what is this chart saying? To help answer this question, review the context surrounding the graph.

Are there any striking visual trends in this chart? Remember that charts and graphs are used to give visual impact to data, so summarizing that at the beginning of your description is a good idea.

Begin by providing the title of the graph, and its main purpose (if it is not clear from the title). Then, describe the its structure and design before going into detail, including the type of graph, and the information on the X and Y axes. You want the reader to understand the layout and larger pieces before describing finer details!

If possible, include the data in a table in a long description.

See examples on Samples of Alt-Text:Graphs and Charts: Short Descriptions or Samples of Alt-text: Graphs and Charts Long Descriptions

Remember:

• Describe only the visual features that convey meaning. Including implied visual impact.
• Focus on the meaning of symbols and not their appearance.
• If the chart is about relationships, describe the relationships and not the symbols.
• This is something that happens more with flowcharts and family trees, you don’t have to describe all the arrows and lines, instead describe the relationships and take advantage of multiple modalities! Lists, nested lists, and even subheadings can help with these types of charts.