Mueller fields many questions related to alt text, resulting in several takeaways about its impact on SEO. Adding alt attributes to an image is recommended from an accessibility standpoint, and it’s helpful for the visitors who rely on screen readers. From an SEO standpoint, alt text is advised when your goal is to have an image rank in image search. As Mueller explains, alt text doesn’t add any value to a page when ranking in Google web search.
Alt Text Is Only For The Image Search
Mueller was asked if alt text should be used for decorative images or not? He considered this a judgment call.
From an SEO standpoint, using alt text depends on whether you care about the images being displayed at the top of the image search. Google doesn’t add value to a page for web search ranking because it has images with alt text.
Mueller advised focusing on its accessibility aspect rather than the SEO standpoint regarding using alt text.
“I think it’s totally up to you. So I can’t speak from the accessibility standpoint, so that’s the one angle there. But from an SEO standpoint, the alt text helps us better understand the image for image search. If you don’t care about your images for image search, that’s alright. Could you do whatever you want with it?
That’s something for decorative images; sometimes, you simply don’t care. You don’t care about the image search for things like stock photos where you know that the same image is on many other websites. Do whatever you want to do there. I would focus more on accessibility than the pure SEO point of view.
It’s not the case that a textual webpage has more value because it has images. We see the alt text and apply that to the image, and if someone is searching for the image, we can leverage that to better understand the content of the image. It’s not the case that the webpage in the text web search would rank better as it has an image.”
The SEO Impact Of Alt Text
Mueller was asked if we should use alt text when the image has text in it? Mueller advises avoiding using text in images altogether. But also said, “Yes – alt text could still assist in this case.”
“I think, if you have text and images, it probably makes sense to have the text directly on the webpage itself. Nowadays, there are numerous ways to creatively display text across the website, so I wouldn’t necessarily try to use text in images and later use the alt text to help with that. I think the alt text is a wonderful way to help with that, but, it’s better to avoid having text in images.”
“From a general aspect, the alt text is meant as a replacement or description of the image, and that’s quite useful for people who can’t look at individual images. Also for those who use things such as screen readers, but it also helps search engines to learn what this image is about.
If you already have a similar description for a product around the image, we have what we need for search engines. For people with screen readers, maybe it still makes sense to have some alt text for that specific image.”
Alt Text Should Be Descriptive
Mueller highlights the importance of using descriptive alt text, and the text should describe what’s in the image for people who can’t view it. Avoid using generic text, like repeating product and service names again and again. To better understand this in detail, check his views on Alt Text best practices.
“In such a case, I would avoid the situation where you’re just repeating the same content repeatedly. To avoid having the title of a product be used as an alt text for the image, instead, describe the image slightly differently. So that’s kind of the advice I would have there.
I wouldn’t just blindly copy-paste the same text you already have on a webpage as an alt text for an image as that doesn’t help search engines, and it doesn’t help people who rely on screen readers.”
