Damon Nelson
You spend an hour on the post. You rewrite the opening line five times. Then you grab the first stock photo that looks close enough and hit publish in ten seconds.
That picture does more work than you think. It talks to Google, to screen readers and to every site that shares your post.
What Google reads in a picture
Google can't look at your photo the way a reader does. Its guide to image SEO says it uses alt text, computer vision and the content of the page to figure out what an image shows.
The same guide calls alt text the most important attribute for giving more information about an image. It also helps people who use screen readers, so a few honest words serve two audiences.
When an image is a link, Google uses its alt text as the anchor text. A picture link with no alt text is a link that says nothing.
Where most featured images go wrong
The first slip is the file name. IMG_4471.jpg tells nobody anything. Google recommends descriptive filenames, so a name like blue-kitchen-cabinets.jpg does real work.
The second slip is overdoing it. Google shows a bad example where the alt text is a long pile of puppy and dog words. That is keyword stuffing, and Google asks you to avoid it. Describe the picture the way you would to a friend.
The third slip is the stock photo everyone else used. If the same image sits on fifty other posts, readers have no reason to stop. Your own photo stands out in a crowded feed.
Last, the picture has to be set as your featured image so it lands in your page's meta tags. Social sites and pin sites read those tags to decide what to show. If it isn't set, they guess.
A four-step check before you publish
- Pick a unique image. Your own photo, or one made for this post.
- Rename the file. Plain words, like coral-desk-laptop.jpg.
- Write real alt text. One honest sentence about what is in the picture.
- Set the featured image and check it. Paste your post's address into Meta's Sharing Debugger and see what title, image and description your page gives off.
That last step is the one people skip, and it catches a blank grey box before a stranger sees it.
This matters even more if you use BoosterPages. Every pin is built from your page's title, featured image and short description, usually read from your meta tags or RSS feed. Each pin carries an image link and a text link back to your post. A better featured image is a better pin.
Once the picture gets the same care as the words, it stops being decoration. It starts pulling its weight everywhere your post shows up.