How to write an alternate text

A great number of pictures are used on the internet, in social media or in presentations. Often an image conveys important information. If you don't want to exclude persons who are blind or with visual impairments, you need to describe visual content. And this means every picture, every graphic, and every gif.

Note: Sometimes pictures are purely decorative and don’t carry any information. It is okay to mark them as ‘decorative’ so the screen reader will skip this picture. This is however not possible in social media.

You want to know how to write an alternate text? We show you!

First the "duty": in a first sentence, briefly and succinctly give the most necessary info you need in order to understand the picture. For your orientation: How would you describe the picture to someone on the phone when you are pressed for time? For example, important context might be the setting, the emotions on people's faces, or the (relative) sizes. Do not use phrases referring to images, such as, "a graphic of" or "an image of”.
Add "additional information": a more detailed description with less important details. For your guidance: How would you describe the image to someone on the phone so that they see it in their mind's eye? This could refer to the background, smaller details in the picture or colours.
Alternate texts are context specific. Depending on the issue, more details might be relevant.
Try to stay as short and crispy as possible.
Use simple, clear language, avoid technical terms and abbreviations.
Keep your own opinion about the picture out of it. Most people want to be able to form their own opinion. Therefore, try to be neutral in your presentation.
A copyright notice has no place in the alternate text.
All text that can be seen in the picture should be reproduced verbatim.
It is always better to include tables directly - not as graphics. For more complex diagrams, a detailed description is recommended, which can be linked below the picture if necessary.
An identical image title following the alternate text should be avoided.
Alternate texts are not only important in the virtual space, but should also play a role in conversations, presentations, etc. Avoid phrases like "As you can see in the picture" and describe directly what you see and read out the text.

How to add alternate texts on Twitter

How to add alternate texts on Facebook

How to add alternate texts on Instagram

For adding alternate texts on MS Word and Powerpoint, please check our basic recommendations for creating accessible documents.

A few more tips for accessible online communication

Hashtags: Start each word in a hashtag with a capital letter and capitalise each letter in an abbreviation. This increases the readability of the screen reader. Examples: #TogetherForParticipation instead of #togetherforparticipation, #CRPD instead of #crpd.
Hashtags should be used sparingly for an accessible post, as the hash is read out as a hashtag or number sign. For example, the hashtag participation (#participation) would be read out as: "Link number sign participation".
Subtitles: Subtitles are not only useful for persons who are deaf or hard of hearing. Using subtitles, more people will understand your video, even without sound. In the best case, write 1:1 subtitles. If you have too much text, try to write the content in a way that makes sense. Each subtitle should consist of a maximum of 2 lines and be visible for about 7 seconds.

References

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