When we create a graphic element with letters or numbers embedded in it, that information often can’t be read by screen readers.
Screen reader users
Guideline 1.1: Non-text content (Situation B)
What to do
If the text is minimal and can be included in a sentence or two of alt text, include it in the alt text.
If it’s too long to be included in alt text, create a long text description of the content, store it in another location and place a link to it below or next to your graphic.
If your description is in a Google doc, we recommend publishing that doc as html and then linking to the html version.