In SEO, how important is it to tag pictures with keywords?

(A real estate agent asked me this question. I answered it in my newsletter and thought I should share here, too!)

Let's forget about SEO for a moment.

You should always add "alt text" on images -- first and foremost for accessibility. I have a friend named John who's blind. He's online every day using screen-reading software to help him "read" content. The software reads and speaks the text on a web page, and when it gets to an image, it reads and speaks whatever is in the "alt text" field. (Every website platform should allow you to add alt text to an image when you upload the image to your website.)

So, the "alt text" should be used primarily to help readers who have vision problems.

Now let's talk about SEO.

You can also include a keyword in the alt text if it makes sense and won't screw things up for people using screen readers.

Example: If you have a flowchart showing the home buying process from one step to the next and it's on your page where the primary keyword is "how to buy a home in Columbus," you can use alt text like this:

"A flowchart that shows the step-by-step process of how to buy a home in Columbus"

That helps vision-impaired readers understand what the image is, and also creates another little signal for Google.

How important is this? On a scale of 1-10 (with 10 being really important), it's about a 2-3 at most. It's just another little signal to help Google understand what the page/URL is about.

BTW, the same thing applies to the image filename. You can name that same image how-to-buy-a-home-in-columbus.png and create another little signal for Google. It's also about a 2-3 on a 1-10 scale. And again, don't spam keywords into image filenames if they don't actually describe the image.