Most webmasters don’t see any difference between image alt text and title, and tend to keep them the same. A great discussion over at Google Webmaster Groups provides exhaustive coverage on the differences between an image Alt attribute and an image title, and standard recommendations of how to use them. In this article, I just want to cover the basics.
What is Alt Text?
Alt text is meant to be an alternative information source for those people who have chosen to disable images in their browsers and those user agents that are simply unable to “see” the images. It should describe what the image is about and get those visitors interested to see it. (Like the picture to the right)
Without alt text, an image will be displayed as an empty icon:
In Internet Explorer, Alt text also pops up when you hover over an image. Plus, Google officially confirmed it mainly focuses on alt text when trying to understand what an image is about.
This means that alt text is valuable for SEO, in addition to being useful for users.
Alt text may also be called an Alt tag or Alt attributes.
What Does Image Title Refer To?
Image title (and the element name speaks for itself) should provide additional information and follow the rules of a regular title: it should be relevant, short, catchy, and concise (A title “offers advisory information about the element for which it is set.“).
In FireFox and Opera it pops up when you hover over an image:
How to Choose Alt Text and Image Titles
So based on the above information, we can discuss how to properly handle both alt text and image titles.
Both tags are primarily meant for visitors (though alt text seems more important for crawlers) – so provide information on the image in order to encourage views.
Include your main keywords in both, but change them up. Keyword stuffing in alt text and title is still keyword stuffing, so keep them relevant and meaningful.
Alt text can get you into trouble if you use it incorrectly, so make sure you are using it to share information and use keywords only when it makes sense.
When choosing Alt tags and image titles, ask yourself the following questions:
- Does this help the user better understand the image?
- Does it include a keyword in a way that makes sense?
- Does the title or Alt tag help search engines understand what the picture is?
Keep in mind; Alt text is meant to help you share more information with users and search engines – so make sure to use the opportunity wisely. For more information, I highly recommend this article by Yoast on Alt tag optimization.