In my experience of optimizing over 300 websites in the last five years, I have found that alt tags don’t make much difference one way or the other when it comes to rankings. Having said that, people ask me about them all the time and so I will cover them in this guide.
Alt tags are an attribute you give to any image on a web page. Their real use is to tell what images are for the vision impaired. Since search engines can’t read what is in an image they look at the alt tag of the image and read that instead.
A popular SEO tactic is to make your key phrases that you are trying to rank for the alt tags of your images. Even though I am not convinced it makes any difference I will show you the proper way to do this.
Let’s say you have an image of a dry cleaning machine. The code would look something like this:
<img src=”images/drycleaningmachine.jpg” height=”400” width=”300” alt=”Dry cleaning machine”>
You’ll notice that I made the alt tag say “dry cleaning machine” this is both accurate because that is what the picture is of and it is short which is what your alt tags should be.
I have seen alt tags that are basically including every key phrase the person wanted to rank for. This can be considered keyword spamming and you could get penalized for it.
