What is Image SEO
Whether they’re graphics or photos, most web images can benefit from a little SEO. If you take just a few steps when uploading, your ranking will reward you for your efforts.
Simply put, image SEO is the practice of sizing, compressing, formatting, and labelling images so they’re most useful for, well, everyone. Taking a few simple steps when uploading images makes your page load faster, takes pressure off of your server, and gives your visitors a better user experience.
In the timeless words of Indigo Montoya, let me sum up…
Make sure images are the right size
Larger files are slower – we all know this. And while we want images to be crisp and clear, we need them to load quickly so viewers don’t click away in a huff.
You only have a few seconds for your page to load before people roll their eyes and move on, so it’s important to increase your page load speed as much as possible. Properly sizing your images will help with this. A lot.
A good question to ask yourself is: what is the largest size the image will display on any screen? The answer to that question gives you the dimensions for your image. If it’s never going to appear larger than 300px wide, make it 300px wide. Simple.
It is possible to change an image’s size inside of WordPress, but I prefer to size images before loading them to the media folder. I use Adobe Photoshop or Illustrator, but you can use any number of apps to change file size, including Paint and Pictures on your PC. If you don’t have an app on your computer, do a search for “free image size reducer” and you’ll get plenty of apps that can help.
If you do want to edit media in WordPress, from the Dashboard go to Media, then hover over the image you want to add words to and select Edit.
File formatting
As of publication of this article, WebP is the recommended file format for WordPress websites. Files in this format are small and load quickly but retain their image quality. A couple of the articles I’ve linked below haven’t been rewritten recently enough to reflect this update, but hopefully they’ll edit and catch up soon.
My website host, SiteGround, gives me the option to change all my images to WebP right in the WordPress interface. To date, my procedure has been to size and save all my images as png’s, upload them to WordPress, then convert them in the SiteGround Optimizer plugin. I’m currently experimenting with saving them as WebP’s right from Adobe, though, so we’ll see how that goes.
Compress images
Compressing images does just what it sounds like; it fits a ten-pound cat into a five-pound box. Smaller file sizes help servers move data faster – the fewer 1s and 0s they need to load, the quicker they can be.
There are so many ways to accomplish compression, but I let WordPress and SiteGround do it for me.
Scrolling back up to the images above, you’ll notice at the bottom of the panel, there’s a field for compression. I set that to high. I also use SiteGround’s Optimizer plugin to compress images.
File names
Here’s a place where most websites can improve their image SEO. How many times have you downloaded a meme to your phone to find the name is an incomprehensible string of letters and numbers? Sometimes the platform you’ve downloaded it from has given it this name, but sometimes it was the people who created the image. They’re missing an opportunity to increase their footprint on the web!
Name your images so they make sense and boost your SEO. File names are seen by people who download them and are an excellent place for you to add your company name, a bit about the image, or a bit of whimsy.
Labeling images for accessibility & SEO
Aside from file names, there are three other places you can add text to images: alt descriptions, captions, and descriptions. These fields help search engines understand your images and they allow those who use page readers know what’s on your site.
WordPress provides a simple and clear interface for adding text to images. The first thing I do when starting a post is to upload images and add verbiage. That way when I’m ready to build my post, they’re ready to go.
From the WordPress Dashboard go to Media, then hover over the image you want to add words to and select Edit.
For more information on how to tailor words for each of these fields, see my post on image labeling here.
Designing graphics so everyone can see them
Designing graphics for colorblindness may not affect your SEO per se, but I can’t write a post on images without mentioning it. When you produce graphics, make sure everyone’s eyes can see all the elements. What does that mean? See my post on images and color blindness here.
Knowledge is power - check out these links!
A quick note here. As of publication date of this post, the Mailchimp and WordPress.org articles I’ve linked below are surprisingly outdated. I’m including them here in hopes that they improve the articles in the future.
- 18F’s Images
- American Foundation for the Blind’s Writing Effective Image Descriptions or "Alt Text"
- Google’s Google image SEO best practices
- Mailchimp’s How to Optimize Images for Your Website
- WordPress.org’s Image Optimization
- WordPress.org’s WebP images in WordPress
- Yoast’s Image SEO: Optimizing images for search engines
