When Twitter announced alternative text for images in early 2016, the web accessibility community was abuzz with conversations.
The long-awaited option, providing the option to add alternative text to images, was greeted with loud approval from Twitter users looking for better web accessibility for the popular social media channel.
I know, I was one of them!
Finally! Twitter makes images better for the visually impaired https://t.co/QWdo1l6Lhy #a11y <- only for iOS and Android apps
— Deborah Edwards-Onoro (@redcrew) March 29, 2016
What is Alternative Text?
Alternative text, also known as alt text, is a text description added to non-textual content.
Think of photos, diagrams, and illustrations. Alt text provides information about the function and content of images.
Which makes the content accessible to people who are blind, visually impaired, or use assistive technology.
In addition, alt text is displayed on the web when images aren’t downloaded. For example, in your mobile email application, when you have images turned off.
Alt text also provides semantic meaning to search engines who can’t “see” images.
While alt text has been a standard for images on web pages for years, social media applications have been slow to support it.
Why Were People Celebrating?
Until early 2016, there was no option in Twitter to describe images.
If someone added a photo to a tweet, but didn’t provide any explanation of what the image was about, people who could not see the image had no idea what the image was.
Since Twitter is a very visual application, people with visual impairments were missing much of the content that was shared on Twitter.
When Twitter announced alt text support for images, users who had been asking about it for years, were thrilled to try it out.
Including me.
First tweet with an alt on a photo #a11y @Jennison how does it read? pic.twitter.com/A8mMeuuSeN
— Gen-axe-er (@dylanbarrell) March 29, 2016
Trying out the new alternative text option feature on my Twitter app. pic.twitter.com/SQmiLv4uWI
— Deborah Edwards-Onoro (@redcrew) March 29, 2016
And then came all kinds of questions:
- Do I need to do something to enable alt text?
- Does alt text work on Twitter apps?
- Does alt text work with Twitter on the web?
- How many characters do I have for alt text?
What to Know About Alt Text in Twitter
As is often the case on Twitter, lots of people jumped in to test the alt text option.
Some things worked, others didn’t.
Over the years, additional alt text support was added to Twitter, making it more fully-featured.
Here are the latest features for Twitter’s alt text:
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As of May 27, 2020, alt text is enabled by default on the web as well as in iOS and Android apps
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Alt text can’t be added to previously published tweets
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You can add alt text to animated GIFs on the web as well as mobile apps
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Your Twitter archive includes alt text that’s been added to images
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You can add up to 1000 characters of alt text to an image.
Note: just because you can add that many characters doesn’t mean you should. Alt text is meant to be concise and descriptive.
However, if the image is complex, you’ll want to provide a complete description. As NASA did in their alternative text for the first images from the James Webb Space Telescope.
Check out tips for creating visual descriptions from Shaun Lauriat’s talk on How Learning American Sign Language Improved my Alt Text.
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Twitter has online help for adding alt text (or what they call “image descriptions”).
You’ll find specific instructions for iOS, Android, Twitter for web, VoiceOver for iOS, TalkBack for Android, JAWS, and NVDA.
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As of April 7, 2022, images with alternative text will display an “ALT” badge in the left bottom corner of the image (both web and mobile).
When you select the badge, the user-supplied image description will display.
For anyone who prefers to view alternative text in desktop Firefox or Chrome browsers, without having to select a button, look into the free Social visual alt text add-on/extension created by my friend Nick DeNardis.
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When you leave the alt text empty for an image, Twitter adds “Image” as the alt text (exception: note number 9 in this list)
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Do you often forget to add alt text to images in your tweets?
As of July 13, 2022, you can set an image description reminder in Twitter that tells you to add alt text before you tweet. -
Developers having questions about alt text or the API endpoint can visit the Twitter community developer forum.
Summary
Like other Twitter users, I’m glad Twitter has continued to improve their support for alternative text for images.
It makes my favorite social media channel even better.
A more accessible product means more people can enjoy Twitter. That’s a win-win for everyone!
Originally published March 30, 2016
Doesn’t do much for the twitter cards, which give a title tag ‘view on twitter’ which you need to do to see ‘purple krokuses in bloom’.
One step at a time, I guess.
Thanks for your comment, Bill. Hmm, have you shared your info with the Twitter accessibility team at @a11yteam or @todd who works on Twitter’s accessibility team?
Nope, just discovered it today on your post. I don’t usually ‘expect’ alt tags, since I’m not a sr user, and don’t have native ‘discoverability’ of alt tags in my browsers.
Aha. I’m using the Jetpack plugin for Twitter Cards. Wondering if Jetpack devs still need to implement Twitter’s changes from last week?
The cards, and the api support alt text.
https://blog.twitter.com/2016/alt-text-support-for-twitter-cards-and-the-rest-api