If you’ve done any reading about SEO tactics over time you’ve likely heard of Alt tags and images. But beyond the superficial advice to load your keywords into the Alt tags, you may be wondering what separates a “meh” Alt tag from a good one.

The simplest way to write better Alt tags is to remember that Alt tags were originally created for accessibility purposes. When a visually-impaired visitor lands on your site, Alt tags can be read aloud by the computer to describe the images that appear on the page. Images they may have difficulty seeing or understanding without.

That said, ask yourself this: Is what you’ve entered as that image’s Alt text a good description for such a person? Would they understand what’s going on? Would the context make sense?

You can usually do this in about the length of a simple sentence, and it’s also pretty straightforward to include major keywords in that tag.

For instance, say you’re writing a post about strength-building tips for people looking to get in shape. Let’s say your first major image is one of an athletic person curling a barbel to illustrate hard work but also the strength of his arm. You might use Alt text like, “Athletic man building muscular strength with intense curls.”

It mentions your core topic of strength building for Google, but also adequately and legitimately describes the image for a blind individual along the lines of how a seeing reader would interpret the image.

Making sure all your site images have Alt text has a cumulative effect.

It’s worth stressing that Alt text isn’t something that will single-handedly make a huge difference in itself, especially in the context of one image.

But, anecdotally we have seen websites with no image Alt text whatsoever see fair improvements in core keyword groups simply by going through the site in a bulk session and writing Alt text for every image. It can be a time consuming process if it’s a site that already has a bunch of images.

If it’s a WordPress site, you can simply enter the Media Gallery and start from one end on the image edit window, write Alt text, and hit ‘next’ to view the next image. That’s probably the fastest way to do it.

Because of the descriptive nature of good Alt text, we don’t recommend relying on SEO plugins like Yoast to handle Alt text for you.

Doing that can be a quick fix for when you’re editing a site that might have hundreds of images, products, and blog posts. That’s a daunting task if most of them are missing good Alt text, and having at least something semi-relevant placed for all of them in a few clicks is a good first step.

But we’d definitely recommend manually going through them some time thereafter to write something custom.