How to write alternative text

Alternative text, often referred to as alt text, is a short description of an image for screen readers to read out loud. It’s also shown in place of images if they can’t be shown for some reason, like a slow internet connection.

Alt text should be short and simple. Here are some tips for writing alt text:

• Imagine you're describing the image over the phone.

• Don’t go into too much detail if it isn’t relevant.

• Think about context. A group of people at a funeral would be described differently than a group of people at a party.

• If an image contains text, write the text out in the alt text. In general, avoid having text in images.

• Don’t start with ‘a picture of..’ or ‘an image of..’.

• You do not need to use full stops.

Not all images need alt text. If an image is just there for decoration, such as background images or graphics, it should be marked as ‘decorative’. This means it won’t be read out by a screen reader.

Image descriptions

Image descriptions are used to describe an image in more detail and are usually written at the end of social media posts. Alternative text is often hidden from view for screen readers, while image descriptions can be read by everyone. It’s especially important to use an image description when there is text in an image, as people may struggle to read the text if the display is very small.