Google On Solving How to Write Good Alt Text
In a Google Search Off the Record podcast, Google’s Lizzi Sassman and John Mueller discussed writing alt text and shared the thought process behind exceptional alt text.
The conversation that followed revealed that there are issues that need to be considered, such as:
Google’s Lizzi Sassman begins the discussion by considering what is the best approach to writing alt text, and wondering if it’s right to be descriptive, or if there’s another way.
Lizzi Sassmann:
“What if you have alternative text but you’re not sure if it’s good?
It could be improved in terms of description, or it describes the picture but not necessarily in the best way?
Because once you start sitting down and actually writing the alternative text, you realize that you could say many things, e.g. B. “Oh, it’s a search result” or you describe something that happens.
Maybe it’s a diagram of how search works, like something that describes a concept.
Or it’s a picture from an event or something.
Do you approach it by describing what’s in it?
Or are there other strategies we could use to improve the words we use for a particular image?”
Accessibility and alt text
John Mueller addresses the issue of accessibility and alt text.
The purpose of alt text in images is to provide a way for audiences with screen readers to understand the images.
Something to help understand how alt text and accessibility intersect is provided by the official standards body for HTML, the Worldwide Web Consortium (W3C), in the form of a little trick for writing alt text for accessibility purposes.
“Imagine reading the website aloud on the phone to someone who needs to understand the site.
This should help you decide what information (if any) or functionality the images have.
If they don’t appear to have any informative value and aren’t links or buttons, it’s probably safe to treat them as decorative.”
Johannes Müller commented:
“So I think you have to look at accessibility… I don’t know… Like everything about accessibility.
So this might be something to check out with someone a little more knowledgeable on the accessibility side.
For example, how alt text should be chosen.”
Alternative text and image context
John next discusses alt text from an SEO perspective.
He continued:
“From an SEO perspective, my recommendation is always to add context to the image in the alt text as well.
So if you have a photo of a beach, don’t just say, “Oh, that’s a photo of a beach.”
It’s more like, “This is the beach before the chemicals ran out.” And…
Because it’s a whole different context, when someone is looking for a beach for a vacation, it’s like, “Oh, I want to see a nice beach. I’m going on vacation there.’
And when you realize that this actually happened before the chemical spill, it’s like, “Well, maybe something like that would lend itself to different types of searches.” “
John then focuses on figuring out what users expect from images that show up in Google image search.
He explained:
“Because ultimately, when you talk about image search, people don’t want an image, they want information associated with that image.
They want to somehow understand a certain topic in order to find information.
And you can provide that extra context in the alt text.
And that’s something they might be looking for.
And if they’re looking for it, make it easy for them to find it.”
Lizzi Sassmann replied:
“That’s right.
And context around the image too, because you don’t necessarily need to put everything in the alt text.
It could be the heel that introduces the beach.
And it can have more information about where it happened, like what beach we are on and what year it was, and all that stuff.
And use that real estate around the image because you don’t necessarily want a huge paragraph of alt text either.
…Right?
And how do you know which text goes where?
But I think providing context is always good to introduce the thing to screen readers too, because it’s like reading top-down.
So if there’s some text in front of it to prepare you, like, “Alright, that’s it…” I don’t know… “Background on what happened before the oil spill.”
And now it’s the beach before the oil spill, more information, and then the beach post… no, during the oil spill.
And then the cleanup… I don’t know… stuff like that.”
Johannes Mueller:
“Something like that.
So if you look at the search documentation and you have an example of a screenshot with a recipe result, you could provide additional context, I think, in the alt text where you say ‘This is a recipe result with these five fields.’ “
Lizzi Sassmann:
“Yeah. And, I mean, that’s… Even the way you phrased that sentence there.
For example: “This is a Rich Recipe result.” That’s probably not the best alt text because it’s like a whole sentence.
It begins with words that have nothing to do with the subject.
And maybe people who also use screen readers would just skip it.
So one of the best practices is not to start each image with a screenshot of, a screenshot of, because then it’ll just be repetitive.
We are already aware that it is an image. You don’t have to say, “It’s a picture of” and then the thing.
Just start with the description. And I don’t think it has to be a whole sentence.
It could be like a descriptive sentence. It doesn’t have to be a complete thought, I guess.”
Descriptive sentence with context
An interesting takeaway from this podcast discussion is to think about the context of the image to write a descriptive sentence for the alt text.
The other notable takeaway is to avoid writing alternative text with words that indicate it’s an image or screenshot, but rather to focus on the context of that image within the overall meaning of the webpage. So if the website is about the ecological damage caused by an oil spill and the picture shows a beach in front of an oil spill, then that’s the context.
Citation
Featured image from Shutterstock/Cast Of Thousands
Listen to the Search Off the Record Podcast starting at minute 11:53