Search engine optimization is about optimizing the content on websites, including images. How can images be made more user-friendly and even help achieve higher rankings on Google? This happens through effective use of alternative image text, often called ALT text!
What is ALT text?
ALT text is also known as alternative image text, ALT attributes, ALT descriptions, etc. Technically, it is part of the HTML code that describes the appearance or function of an image on a website. Alternative image text should only be present in the code, and is not the same as regular image captions that are often shown in newspapers. Alternative image text is most often added in the site’s editing platform, and it explains what the image is about. This is primarily a tool to improve website functionality for users with visual impairments or for those who have disabled image display in their browser. ALT text is read aloud by screen readers. It increases web accessibility and helps ensure optimal universal design. All images that are part of the page must have an ALT attribute, meaning there should be a field in the code dedicated to ALT text. However, not all types of images should have text written there. If the image is purely decorative, for example as part of a menu or the site’s graphic design, the ALT text should be empty. The element must be present in the code, but it should be empty after “alt=""“.
Why is ALT text important for SEO?
Using alternative image text not only makes the content on the page more accessible for visually impaired users. Search engines also use the ALT text as a factor to understand what is shown on the page. Google is getting better and better at interpreting what the content on a page means, but the search engine(s) still rely more on text than on images. ALT text is therefore considered part of On-Page SEO, the optimizations you make on your website. By being able to read images more easily, Google can also more effectively match images to a relevant search, which means that images with ALT text can contribute to more relevant impressions of your page. It’s not an absolute rule, but it’s certainly reason enough not to postpone using alternative image text!
How to write ALT text?
There are various guidelines for creating alternative image text to ensure it is read as effectively as possible by users and Google. Here, we walk through some of the most important ones:
- Describe the image content clearly: When writing ALT text for a decorative image, it is important to describe the appearance of the image as clearly as possible. Use concrete descriptions of what can be seen in the image.
- Short and concise is best: Keep the description as brief as possible. Do not use more than 100 characters. This makes the image’s message clearer.
- Don’t use it as an opportunity to keyword stuff: It definitely makes sense to use relevant search phrases in the image description, but do it in a natural way. Don’t cram it full of keywords just to include as many relevant phrases as possible.
- If it is a link, describe the purpose of the link in detail, not the appearance of the image: If the image is the main element in a link to another URL, it is important that the ALT text reflects this. It is also important that the description of the link is as specific as possible. Not just which website it links to, but what the specific page is about.
- Describe the most important information first: As in a news article or press release, it is important to include the most important part of the description first.
- Remember to describe what type of image it is: Since the alternative image text is an assistive tool for people using screen readers, it is very useful to include what type of image it is. Is it a graphic illustration, a drawing, or a photograph? Still, remember to place this kind of information at the end. The subject of the image is the most important.
Summary
ALT text is essential for making your site more user-friendly for people with visual impairments and users of screen readers, in addition to being an SEO element that can help improve your rankings on Google. By writing specific and well-described alternative image texts, both screen readers and Google’s crawlers will read and understand the page better. There is therefore no reason not to use ALT text actively.
