Website Image and Media Tips
The HTML code for images displayed on a website includes what’s known as “alt text”, which screen readers use to describe images for visitors who are unable to see. Using appropriate alt text is also important for search engine optimization since search engines can “read” the text and therefore better understand the content of a page.
There are a few key points to note when adding alt text for an image:
Keep the text brief and focused on the purpose and content of the image.
Alt text should not begin with phrases like “A picture of” or “Image of”. This is unnecessary since screen readers will already identify the content as an image.
If an image is purely decorative and not relevant to the content of the page, then the alt text should be left blank.
Alt text can also be added directly to the page under or near an image, in which case you don’t need to add the text for the HTML tag since this information is already available on the page.
If an image is also a link, then the alt text should describe the function of the link (though it’s better to include a text based link instead of linking an image).
It’s easy to add alt text to image elements on your website. Simply click on the image element to bring up the options, and then click on advanced – you’ll find the alt text field there. Don’t forget to publish your site again after adding alt text to any images. Find out more in our help guide to images or get a more in-depth look at using alt text correctly at WebAIM’s page on alternative text.
If your website includes video or audio, you can add captions and create transcripts to make them accessible for all users.
If you’re using YouTube to host your video, it’s very easy to add captions - in fact, YouTube even provides an automatic captioning option for videos in several languages. This is based on speech recognition, so it may not provide perfect results, but you can review and edit the captions once the video has been processed. Learn more about YouTube’s automatic captions here.
Vimeo also allows you to add captions for your videos, though they do not provide an automatic captioning option. Check out this Vimeo help guide to learn how to add captions to a video hosted with Vimeo.
It’s also possible to add subtitles directly to a video file, but this option requires video editing software and is more complicated and time consuming. If possible, you should try to host your video at a site like YouTube or Vimeo that makes it easy to add captions.
You can also create text transcripts for audio on your site. These do not need to be verbatim, but should convey the content accurately. If your audio file is short, you can transcribe it yourself the old fashioned way by listening, pausing, typing what you heard and repeating that process until you’re finished. For longer files, you may want to consider looking into a service such as Trint that will automatically transcribe audio files that you upload. You will still need to review the transcripts and make corrections where necessary, but this is big time saver for lengthy recordings.