Accessible Internet: Writing Alt Text for Images

Ipek from Supersense
3 minutes reading time
January 24, 2020

How many content creators add alt text to their visual content when publishing them on either social media or on their websites? Most people do not even write captions about what the image is actually about, even making it a mystery for their sighted peers. Sometimes the pictures, photos, or other visual content is named as something like IMG-63969. And when the website or image does not load properly, what you see is that awkward random name, and more often than not, screen readers do not pick this up at all.

example website codes on a screen, code text blurred towards the end.
Photo by Lavi Perchik on Unsplash

Alt Text and Captioning

Alt text is the textual description of the graphic content on the web, including social media posts. Screen readers “read” this when alt text is provided, so the visitor would know what the image contains. Therefore alt text should be added “into the image” to describes the content. Penn State University provided some excellent guidelines about what alt text is and how it can be integrated into a website.

To be clear, there are different types of descriptive text that need to be added to visual content, and alt text is only one of them. There is also the caption that is different from the captions in Instagram posts, which usually contains ironic or funny stuff that almost entirely changes the context of the image presented.

The visual content added to the webpages usually requires both alt-text and a caption, which are completely different things. When appropriately used, the caption is generally placed right under the picture, table, figure, etc., that tells the reader the source of the image, where it is taken, to whom it belongs, etc. It does not describe the content, and it is simply something like a heading.

Captions are also commonly used in books, magazines, newspapers and museums, and art galleries. I am pretty sure that some of you have stumbled upon an artwork that is captioned as “Untitled 4.” Quite clear, isn’t it? This is where alt text comes into play. The artist might not want to give the art piece a title, which is perfectly alright, but a sighted person can see the artwork itself and form an opinion, whereas a blind or visually impaired person cannot. If there won’t be alt text that describes what’s going on, then there is no artwork for a person who can’t see. To overcome this, museums are doing some work to make art more accessible to blind people.

Writing Good Alt Text

Adding alt text is great, but adding good alt text is awesome. Most social media platforms limit the alt text to 1000 characters, LinkedIn even decreased it further down to 120, which makes things more difficult.

However, short does not always mean bad. The alt text should describe what is going without speaking in circles, so no tiny details. To capture the main idea is usually enough, especially when there is the text accompanying the image.

Starting with “picture shows a tree,” “a picture of a dog” does not really help to describe the content, and using these fillers makes you lose the precious characters that you are allowed to use. Also, if you’re a content creator, don’t see alt text or caption as an opportunity to load more keywords.

Good Practices

Shannon Finnegan and Bojana Coklyat are disabled artists and activists, have a project called alt text as poetry, in collaboration with Eyebeam and the Disability Visibility Project. The project aims to increase website accessibility by implementing an out of the box way of thinking about alt text. They prefer to approach alt text as poetry and found similarities between the two of them in ways of using the language: economic and experiential.

Another good practice is the “oh caption, my caption” chrome extension, which is created with the motto “Crowd-sourced image descriptions: Sighted people helping visually-impaired people get the most from social media.”

To wrap up, paying attention to the website and social media accessibility is one of the first steps towards a more inclusive internet experience. Also, writing alt text doesn’t take long. In fact, who knows, as, in the alt text as poetry, it might trigger an artistic endeavor.

An illustration of a smartphone

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