Digital Accessibility: Images

Alt text (alternative text) is a description of an image or other non-text content on a webpage. Using images in web pages can make content more desirable and easier to understand. To ensure accessibility for users who are visually impaired, it is important to provide information to describe the image. Not only it will help to meet accessibility standards, but alternative text can help all users get a better understanding of what is being portrayed on the page.

The alt text should have the following:

• Accurate description: The alt text should accurately describe the contents of the image or non-text content. This helps users who are visually impaired understand what the image is conveying
• Brief: The alt text should be brief and to the point, as longer descriptions can be difficult for screen readers to process. A general guideline is to keep alt text under 125 characters
• Avoid redundant phrases: Avoid phrases like "image of" or "graphic of" in the alt text as these add no additional information and take up valuable character space
• Provide context: In some cases, providing context for the content can be helpful. For example, if an image is a chart or graph, the alt text could describe what the chart or graph is showing
• Null value for decorative images: If an image is used purely for decorative purposes and does not convey any meaningful information, the alt text should be left empty or use alt="".  Screen readers will then skip over these images, saving time and avoiding confusion for users who are visually impaired

By following these guidelines, you can ensure that all images and non-text content on your website are accessible to users with visual impairments.

Guide on images by the Web Accessibility Initiative