KickstarterForum.org

By adding alt text and image descriptions, barriers are lifted and more people can access your content.

Alt text tells people what is in an image, such as text or basic essential details. If an image fails to load, alt text will display in its place. Search engines also index alt text information and consider it a factor when determining search engine ratings.

An image description gives more details than alt text and allows someone to learn more about what is in an image that goes beyond alt text. Alt text gives the user the most important information while image descriptions provide further detail. For example, alt text tells someone that there’s a puddle on the floor, and image description tells someone that the puddle on the floor is in the middle of the floor and it’s orange juice.

People with vision impairments such as low vision and blindness may use screen readers in order to access the internet, or just have trouble distinguishing images. Screen readers will read the alt text out loud, as well as image descriptions, depending on what settings the user has enabled. Alt text and image descriptions can provide essential information such as text, links, and image details.

One should also use alt text in social networking posts. When you add a picture in Twitter, for example, it gives you the option to add a description.

I’ve found that keeping alt text short and clear works best, then using a longer description only when the image really needs it. I picked up that habit while working with an seo agency for ecommerce, since they pushed me to think about both accessibility and search traffic at the same time. Once you get into the groove, it becomes second nature and saves a lot of cleanup later.