Guidelines for Alternative Text
Difficulty: Advanced
Category:
- Content
- Presentation
Alternative text for images can be presented either in the alt attribute of the image (<img alt=”Acme Logo” src=”logo.jpg”>) or in text near an image (e.g., an image text caption). When a caption or surrounding text provides the full content of the image, the image can generally be given a null or empty alt attribute (alt=””) to avoid redundancy. Screen readers identify the presence of images, so it is not important to indicate in alt text that it is an image (i.e., avoid “image of…” or “graphic of…”), however it may be useful to inform the user if an image is a photograph, illustration, chart, etc. if this information is considered central to the content of the image.