Alt Tag Explained

Michael Buczek - May 29, 2008

In my last few posts I have covered the different types of metadata and how to use each effectively. In this post you will learn about the “alt attribute” or more commonly called the alt tag. The alt tag is html code we use to label images found on websites.

If you view a site’s source code and look for an image, you will most likely see the name of the image in gif format and next to it will be the alt= tag. This is where you can label your image. Example: Alt Attribute example:

You might be asking yourself “What is the importance of the alt tag?” Good question! The alt tag is important for three distinct reasons:

1. Some searchers turn graphic functionality off so a page will load faster if they have a slower connection speed. When this is the case, the image will not appear, but rather the image’s alt tag will be viewable.
2. It’s used for blind and visually impaired readers who access a page using audio-based browsers, or screen readers. — These devices read the page aloud so the user can hear the content on the page. If there is no alt tag, the images will be skipped and important information could be lost.
3. Universal Search — This has been around for about a year, and is still evolving. Universal search uses alt tags and other information to display the images of your website in the “blended results”. These blended results feature images, video, news and regular listings in the search results. The search engines’ algorithm takes alt tags into account when displaying these mixed results.

Alt Tag Tips
While it is important to realize that the alt tag should be used for all of the images on your site, you should not over use this tool. Abusing this tag can have serious consequences when it comes to the search results. Below are some do’s and don’ts to creating effective alt tags.

Do’s
– Use on every image on your site
– Describe what the image represents
– Use keywords where applicable
– Make sure each image has a unique alt tag

Don’ts
– Don’t stuff all of your keywords into the tag to “game” the search engine — This is called alt spam
– Don’t add alt tags for things like buttons and images smaller than 10 x 10 pixels. These items are not necessarily important to search, so you don’t have to label them.

As always, alt tags are not the “SEO Golden Ticket” but rather a piece of the bigger picture. Work on Metadata and alt tags, and you will be one step closer to having an optimized website.