Is the alt text 150 characters or fewer?

Goal

Ensure that alt text is short enough to be usable

Why this matters

Some screen readers, such as JAWS, cut off at 150 characters of alt text and the user has to take an action to hear the rest of the text. When alt text is being read, the user can’t pause the read-out if interrupted. See Image alt text and SVG titles for more details on why want short alt text.

How to test

1. During draft: do a character count on the content to ensure it’s under 150 characters.
2. Listen to the page on a screen reader to ensure that the content is fully read aloud.