How to Use Alt Tags for Accessibility
December 27, 2018
The internet provides the most dynamic resource for research, education, and entertainment of all kinds. Nothing else has changed the world for the better as much as the internet. However, it’s important to create web pages accessible by all. Properly using alt tags for accessibility ensures that your website will be more accessible to the visually impaired.
Using alt tags for accessibility may seem challenging at first, but with a little education, anyone can learn to intuitively use alt tags on their website.
What are alt tags?
Alt tags are bits of code included in HTML that look like this;
Web designers use alt tags in their web page code in order to detail the subject matter and context of images on a page. The primary function is describing images to users who can’t see them. This includes visitors using browsers or screen readers that block web images, but more importantly, alt tags allow the visually impaired to identify the contents of images.
Additionally, if an image file cannot load, a web page will display the alt tag, allowing visitors to identify the subject of the picture. Search engines also read the description provided by alt tags to help rank the page in relevant search results.
Most importantly, including alt tags for accessibility guarantees that all visitors, even those with visual impairment, can get the most out of your web pages!
Best practices using alt tags for accessibility
When using alt tags for accessibility, use thorough descriptions that accurately depict the image contents. Anyone reading the alt tag text ought to be able to reasonably envision the described picture. Remember, alt tags function primarily to provide text detailing images to those who cannot see them. Although thorough descriptions are important, try to stay concise. Many popular screen readers only read up to 125 characters of alt text, so try to use fewer characters than that.
In your alt tag description avoid using phrases such as, “picture of,” “image contains,” or similar expressions. Your alt text already refers to an image, so specifying it isn’t helpful. Remember to describe the contents of the image, not the appearance. Try to describe what’s important about the picture’s subject matter, not simply what the picture looks like. For example, a picture of daffodils is better described with an alt tag that reads, “daffodils in ceramic vase,” than an alt tag that reads, “pretty yellow flowers.”
Decorative images, like borders or spacers, do not necessitate descriptive tags since these images present no information. In these cases, use a null alt tag, like this one;
Though no description is necessary, the best practice is to include the tag.
This differs from images that perform a function, such as form buttons. If you place a form on your website that uses images for buttons, like a submit button, include an alt tag for them. These tags should describe the button’s function, such as, “submit form,” or “sign up.”
Web designers should always include alt tags for accessibility, but they can serve additional purposes. Most notably, alt tags play a role in raising a web page’s search rankings. By including a relevant keyword within the alt tag, a designer can improve a page’s SEO. Of course, this shouldn’t supplant the use of alt tags for accessibility. Instead, effective writing allows a web designer to use a focus keyword while accurately describing an image’s contents.
While using alt tags can improve search engine ranking, never abuse this feature. Use keywords selectively, and always as part of an accurate description. Don’t use a bunch of variations of a keyword in your tags; this is called “keyword stuffing.” Not only will this negatively affect your search rankings, but it defeats the purpose of using alt tags for accessibility. By all means, use your keyword within your alt tags when appropriate, but only as part of an effective description of your image.
Alt tags for accessibility make the web a better place
Using alt tags effectively makes web pages accessible to all visitors. This means that the visually impaired and users of older browsers will better understand all the information presented on your web page. The internet provides so much information, both educational and entertaining, that we should all strive to deliver a web experience accessible to all. Combine alt tags with an accurate description of images to ensure that all who visit your site have access to all the information presented.