Alt text character limit?

Does anyone know if there is a limit of how many characters you can input into the Alt Text option for images? I used alt text for a fairly lengthy description of a diagram that needs to be accessible with a screen reader in my course. It allowed me to input all the characters I wanted. But when I published it and tested it with JAWS, it cut off reading all the alt text I entered. 

I think it would be a helpful solution to make the alt text box larger and identify a character limit, if there is one, under the box so the user is aware of how much they can input into alt text. 

If anyone knows about this topic I would love to hear from you! Thank you in advance!

6 Replies
Crystal Horn

Hi there, Laurie.  Thanks for reaching out!  It looks like our support team is going to work with you on this issue where some of the alt text is not being read by JAWS.

In short, what we understand currently is that none of Storyline, HTML or JAWS has a character limit on alt text.  Our team will help test your output to better understand the cause.  Watch for an email from them soon!

I'll follow along with your case as well.  ☺️

Bob O'Donnell

Best practice for Alt Tags is to keep them short and succinct. If you have something that requires more than a short sentence you should provide the user with an alternative descriptive option. In your case, you could provide a hidden link to the diagram description that only a screen reader would pick up.

Laurie Necasek

Thank you Bob for your feedback. I definitely try to keep alt text short and sweet but in this case I had to describe a diagram in words. So it required more characters than normal. I added a button on the screen that I called "diagram description" so that anyone can click it and hear the description of the diagram. The whole course is narrated with SL's text to speech so the learner is already used to the audio being played in the slide. Thanks!