Let’s talk about Image Alt Text and how it relates to SEO. The alt tag in images is what you use to describe an image. You do this so screen readers and visually impaired viewers have a reference for the image, and also so search engines know what context the graphic was used in as well.
Let’s talk about keyword factors of SEO (search engine optimization) for a page or post:
-keywords in the URL
-keywords in the HTML title
-keywords in the page header
-keywords in the text
-keywords in links back to the page
-keywords in directory names
-keywords in filenames
-keywords in image alt text?
It’s widely known that all the points mentioned above (combined) make up SEO for a page or post, but the “image alt text” has been debated by SEO professionals for years. I personally have been using targeted keywords in my image alt text for years, and my experience has been that it does make a difference. There are times when I’ve not used it (when I could have). I hadn’t thought much about whether it was an SEO value that influenced SERP’s until I read this post at Webmaster magazine. In that post Peter did some informal research which blatantly showed how alt text was a very determing factor for search rankings (on the keywords he checked).
First, let me say that I mentioned long ago what a great resource Webmaster magazine is. Signup for Webmaster magazine for free. You’ll get both the digital version and 4 print magazines per year for absolutely nothing. I’ve been a member for 3 years, and that’s where the link above and idea from this post came from. If you’re not already a subscriber, you’ll missing out on a great free resource!
Next – let’s do a little research of our own, shall we? I’m going to do a google search for “Muhammad Ali fight”. I specifically added “fight” to the keyword phrase to see if I got pages with pictures as results.
You would think with a search like this that the number #1 results in SERPs would be the official Muhammad Ali web site and Wikipedia, closely followed by maybe YouTube – wouldn’t you? In this search result the #1 web site just happens to be a boxing memoribilia web site (actually the #1 and #2 results) – and I’ll show you why:
Look at the results above, the order of the search results are as follows:
1. boxing-memoribilia.com (PR 4)
2. boxing-memoribilia.com (PR 3)
3. Wikipedia (PR 6)
4. YouTube (no PR)
5. infoplease.com (PR 5)
6. ali.com (official Muhammad Ali site) (PR 6)
Seems kind of lopsided doesn’t it? It seems like Ali.com or Wikipedia.com would be first. Before I explain (why I believe) it’s this way, let’s look at the google results for only the keyword search “Muhammad Ali”.
The results look a little different don’t they?
2. ali.com official site
4. Google Image search
6. books.google.com (books by Muhammad Ali)
So, how did a little tiny boxing memorabilia web site (with no pagerank) get to the #1 (and #2) slot in google for the search phrase “Muhammad Ali Fight”? I’ll tell you how – RELEVANCY!
As I previously mentioned “alt text” is a hotly contested item amongst professional SEO’s. There is high debate on whether or not it actually makes a difference or not. I’m going to throw my hat into the ring and say – I believe that it DOES make a difference, but specifically for what we call “long tail searches”. Obviously you probably won’t make a dent in the search phrase “Muhammad Ali” by placing a bunch a pictures on your page with those 2 words as the alt text. You can however easily take over the top spot for “Muhammad Ali Fight” if google thinks your site is more relevant!
I want you to go back to that very first image of the search results for the 3 keyword phrase with fight in it and look at it again. See the words that are bold?
Search result #1: All 3 words are in the title and description, and 2 out of the three words are in the domain name.
Search result #2: 2 of the 3 words in the title, all 3 in description, 2 in the URL
Search result #3: 2 words in the title, all 3 in the description, 2 in the URL
Search result #4: all 3 in the title, no description, none in the URL
Search result #5: 2 in the title, 3 in the description, one in the URL
Search result #6: 2 in the title, 3 in the description, one in the URL
It should be starting to make a little more sense to you now, so let’s add in the alt text information for all 6 searches:
Search result #1: header image alt text “Muhammad Ali Bio”, article image with alt text “Muhammad Ali Biography and Fight Record”
Search result #2: header image alt text “Muhammad Ali – Boxer”, article image with alt text “Muhammad Ali Autographs”, article image with alt text “Muhammad Ali Biography”, article image with alt text “Muhammad Ali Pictures”, article image with alt text “Muhammad Ali Quotes and sayings”
Search result #3: ali header image with no alt text, Elijah Muhammad address Ali pic with no alt text, Ali interview pic with no alt text, and 5 more Ali images with no alt text
Search result #4: YouTube dominates this results even though it has no description and not keywords on the URL. The page title is obviously created dynamically on demand for searches
Search result #5: one Ali image with alt text “Muhammad Ali”
Search result #6: every single image has no alt text, and despite the high pagerank the official home page of Muhammad Ali can’t hold it’s own against the lesser PR site
Is this scientific evidence? No. But it seems to me like it’s a pretty good indication that by using keyword laden alt text in the images of your blogs you can do better for long tail keywords. This is HUGE for niche and affiliate marketers.
In my opinion image alt text is definitely SEO!