Is alt text a ranking factor? In today's article, we'll answer the question of whether alt tags affect your organic search rankings (or not). Here's what you need to know.
Alt text is used to help computers read images.
But can alt tags affect your organic search rankings?
Read on to learn if there's a correlation between alt text and improved rankings in Google Image Search results.
The claim: Alt text is a ranking factor
What is alt text?
Alt text is an attribute of an HTML image. It allows you to create an alt text version of your image if it can't load or has an accessibility issue.
Because of its importance to Google Image Search, it is considered a ranking factor.
Alt text as a ranking factor.
Google highlights how alt text plays a vital role in the recognition of your images by Google Image Search.
You'll find an image best practices page in Google Search Central's advanced SEO documentation. In a section called "about alt text," Google discusses the use of alt text.
"Google uses alt text along with computer vision algorithms and on-page content to understand the subject of an image. Additionally, alt text in images is useful as anchor text if you choose to use an image as a link.
Although the company doesn't specify that alt text will improve your rankings, it does warn website owners that improper use can harm your website.
"When writing alt text, focus on creating useful, information-rich content that uses keywords appropriately and is in the context of the page content.
Avoid populating alt attributes with keywords (also known as keyword stuffing), as this leads to a negative user experience and can result in your site being viewed as spammy."
He also offers the following examples of good and bad use of alt text.
Google Sites documentation indicates that images can come with pre-populated alternative text
"Some images automatically include alt text, so it's a good idea to check that the alt text is what you want."
For example, when downloading stock photos, a text description of the image is embedded in the file.
When uploaded to a content management system (CMS) like WordPress, text descriptions may need to be moved to the alt text field or modified to remove unnecessary keywords.
Google Search Central's "Beginner's Guide to Search Engine Optimization" offers the following advice on alt tags when using images as links:
"...if you use an image as a link, the alt text for that image will be treated similarly to the anchor text of a text link. However, we don't recommend using too many images for links in your site navigation when text links can serve the same purpose.
More posts
In 2020. John Mueller, a Google Search advocate, responded to a question about image alt text with a quote during Google's webmaster office hours. In the response, he talked about how Google uses it:
"For Search, what happens with the alt attribute is that we use it to better understand the images themselves, specifically for Image Search. So if you weren't interested in Image Search, then from a Search perspective, you don't actually have to worry about alt text.
But if you want those images to show up in Image Search, which sometimes it makes sense to show fancy quotes in Image Search as well, then using the alt attribute is a good way to tell us that this is on that image and we'll get additional information from the whole page in terms of how we can rank that landing page."
Moz mentions ranking factors for alt text. Instead of saying that alternative text itself is a ranking factor, Moz advises:
"... alternative text offers you another opportunity to include your target keyword. Since on-page keyword usage still carries weight as a search engine ranking factor, it's in your best interest to create alternative text that both describes the image and, if possible, includes the keyword or key phrase you're targeting.
In 2021, during a Twitter discussion about the benefit of ALT text on SEO, Google developer Martin Split said:
"Yes, alt text is also important for search engine optimization!"
Later in 2021, Mueller noted that alt text is not magic during a conversation about optimization for indexing purposes.
"I found out that alt attributes are necessary for HTML5 validation, so if you can't use them with your platform, it sounds like a mistake. However, alt text is not a magic SEO bullet."
Alt text as a ranking factor: Conclusion
Alt text is a confirmed ranking factor for image search only. You need to create descriptive, spam-free alt text to help your images show up in Google Image Search results.
Alternative text is definitely not a ranking factor in Google Search. Google has clarified that alternative text acts like normal text on a page in a full search. So it's not useless, but it's not a separately considered ranking factor in your page content.