Writing alt text for images is an important part of publishing a blog post or other web page. But, as with other extras like the SEO page title and meta description, many people aren’t quite sure of the purpose, or the proper way to fill it out.
In fact, alt text (short for “alternative text,” and also sometimes referred to as “alt descriptions,” “alt attributes,” or “alt tags”) serves a few purposes, and there are of course associated best practices with creating it. It can be added in as HTML, but if you’re using WordPress or another popular CMS, there’s usually a dedicated field for entering the alt text when you select and set the image.
So, once you’ve chosen a great image for your content or copy, don’t overlook or ignore the alternative text. Here’s some information to help you understand the reasons for writing alt text for images and the right way to do so.
Reasons for Writing Alt Text for Images
Descriptive alt text is one of the crucial ways to make a website more accessible. Assistive technology like screen readers will read the alternative text so that visually impaired visitors know there’s an image on the page, and what it depicts.
Alt text also helps with search engine optimization (SEO), particularly when it comes to being found through image searches. The description helps search engine crawlers understand the image and index it properly. This in turn helps it come up when someone searches for an image like the one you’re using.
One other benefit is that alt text can improve the user experience in the event that the image doesn’t load on the visitor’s device. This happens for various reasons, like glitches, images being blocked by a browser or email service provider, etc. The alt text will display in its place, so the user will at least know there’s supposed to be an image there and what it shows.
How to Write Alternative Text for Images
Writing alt text for images is a fairly simple and straightforward part of optimizing your blog posts and other web pages. Here are the key things to keep in mind:
- The main purpose of the alternative text is to accurately describe the image.
- Be descriptive. “Ice cream” is weak alt text, while “Scoops of chocolate ice cream with colored sprinkles in a waffle cone” is much better.
- Work in your primary keyword for the page if you can do so in a relevant, logical way. Don’t keyword stuff, though, and remember that describing the image accurately is the priority here.
- Alt text of up to about 100 characters is ideal; many of today’s leading screen readers stop reading alternative text at 125 characters, so definitely cap it there.
- Don’t include anything like “Photo of,” “Image of,” “Picture of,” “Graphic depicting,” etc. in the alt text. It’s understood by users and search engine crawlers alike that the alternative text is describing an image.
- Remember to include alt text for call-to-action (CTA) buttons, describing its purpose. For example, the alternative text could say “Submit button,” “Learn more button,” “Sign up button,” and so on.