Alternative Text

Alt text (alternative text) provides a text description of images for users who cannot see them. Writing good alt text is a crucial accessibility skill.

What is Alt Text?

Alt text is:

• Read by screen readers
• Shown when images don't load
• Used by search engines
• Required for accessibility

When Alt Text is Needed

Writing Good Alt Text

Good alt text:

• Describes content AND purpose
• Is concise (under 125 characters)
• Doesn't start with "image of" or "picture of"
• Includes relevant text in the image

Context Matters

Decorative Images

Use alt="" (empty, not missing) for:

• Decorative borders and patterns
• Icons next to text labels
• Purely visual embellishments

Images of Text

For images containing text:

• Include all visible text in alt
• Consider using real text instead
• Logos need their name as alt

Complex Images

For complex images:

• Brief alt + detailed caption
• Link to full description
• Consider data tables for charts

Exercise: Write Alt Text

Write appropriate alt text for different image contexts:

Good alt text makes visual content accessible to everyone!