There is an overview on our guidelines for alt text in our Images article.
This information is taken from a post on Hive from the Accessibility Enablement team. To view it on Hive if you are able, the link is What On Earth Is Alt Text?
What On Earth Is Alt Text?
You might have come across the term alt text in a few places now, from us in Accessibility Enablement, on X (formerly known as Twitter) or another social media platform, here on Hive, somewhere on the internet or from somewhere else that you can’t remember. Don’t worry if you haven’t heard of it at all until now, we’re going to explain.
What is alt text?
Alternative text (alt text) is a text substitute for non-text content in web pages, digital documents, ebooks etc. Non-text content can include, but isn’t limited to: photos, images, illustrations, headshots, icons, GIFs.
Why is alt text essential?
Alt text serves several essential functions:
- People who are blind or have visual disabilities use a screen reader to perceive the content and function of images, the screen reader announces the alt text that was written for the image.
- People who find reading large blocks of text difficult or tiring (for example people with dyslexia or eye-strain) might also use screen readers to assist with consuming content online, including images.
- If an image fails to load or a person has blocked images, browsers will present the alt text in the place of the image.
- Search engines use alt text and consider it into their assessment of the page purpose and content.
What’s a screen reader?
A screen reader is a technology that helps people who have difficulties seeing to access and interact with digital content, like websites or applications via audio or touch. The main users of screen readers are people who are blind or have very limited vision.
The technology reads out loud what is on the screen and users can adapt them to their needs, for example you can decrease the speed of speech or change the language. Screen readers allow people to navigate through websites and applications via the speech output. Screen reader users may also use a Braille display instead of speech output.
Nearly all computers, tablets and smartphones have a screen reader function built in. The most popular programs are JAWS and NVDA for Windows computers, VoiceOver for the Mac and iPhone, and TalkBack on Android.
How do you add alt text to images?
Depending on where you’re adding an image, the options will vary. Most content management systems, social media sites, and word processing softwares have an option when uploading images to add the alt text description. On web pages it’s added within the code.
How do you write alt text for images?
Now this is the difficult part, writing alt text for images can be very tricky business depending on the content of the image. The key piece of advice we’ll give here is that context is everything. A single image could have different alt texts depending on what the author wants to convey.
Yes, technology is getting better at recognising what an image depicts. However, algorithms alone cannot understand what an image means within the context of the overall page. Authors must provide alt text that represents the content and function of their images.
So, what is alt text again?
Alternative text is a succinct text description that describes the appearance or function of an image in a digital format. Alt text is essential for people who rely on screen reader technology and for people to understand what is in an image when it fails to load.
For more guidance on writing alternative text for specific use cases, please head over to this blog post: Practical examples of alt text for better accessibility.
Accessibility Enablement is here to help with your alt text questions or any accessibility related questions - you can email us at AccessibilityEnablement@springernature.com, or if you’re on Slack, contact us in #ask-fed-enablement. Slack users can also follow the #accessibility channel for tips, news, and interesting discussions. As always, feel free to ask questions in the comments below!
Extra comments from SNCS:
The content above was written before the majority of the business moved from Slack to Teams. There is an Accessibility space in Teams, and a dedicated Ask Accessibility Enablement channel. Contact Amy Megson if either of those two links do not work and you would like access to the channels.
The post refers to a blog post "Practical examples of alt text for better accessibility", which links to Hive. There is a version of that in our Freshdesk Knowledge Base for those who are unable to access Hive: