Images & Alt text

Image Description Best Practices

Functional Images

Functional images add value to the content because they provide more information than can be provided through text alone.

Altenative Text

Alternative text (or alt text) is text that describes a functional image. It makes it possible for people using assistive technologies to access the information conveyed by an image. It also helps search engines better understand the purpose of the image.

Include long descriptions for complex images

Long descriptions explain information that is presented in complex infographics or images. You must provide a long description if you can't describe the content and function of the image in less than 140 characters. If you can describe the image in less than 140 characters, use alternative text instead. If a detailed and equivalent explanation of the image appears in the text immediately before or after a complex image, you don't have to provide a long description.

A balanced scorecard showing how business activities align with an organization's vision and strategy to monitor key performance indicators. Extended description available below.

A balanced scorecard is a strategic planning and management system used worldwide to align business activities with an organization's vision and strategy.

Business activities are grouped into 4 perspectives, all of which are interdependent and come from the vision and strategy. These are learning and growth, internal business processes, financial, and customer. Each has a question associated with it.

  1. Learning and growth: To achieve our vision, how will we sustain our ability to change and improve?
  2. Internal business processes: To satisfy our shareholders and customers, what business processes must we excel at?
  3. Financial: To succeed financially, how should we appear to our shareholders?
  4. Customer: To achieve our vision, how should we appear to our customers?

Each perspective can be monitored using the following 4 components:

  • objectives
  • messages
  • targets
  • initiatives

Decorative Images

Images that are for decorative purposes only don’t require alt text.

Here’s when we consider an image decorative:

  • The image doesn’t provide important context to the page content
  • The image isn’t used as a link to direct people to more information

Alt Text

When you're writing alternative text for a functional image:

  • Describe the image as if you were describing it to someone over the phone
  • Limit the text to around 140 characters (including spaces)
  • Use the text that is embedded in the image only if it provides enough context; otherwise, write different text that includes more information
  • Don't use "image of..." or "graphic of..." to describe the image; screen readers do this already