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Specialized SEO

Alt Text (Alternative Text)

Definition

Descriptive text added to image HTML that describes image content for screen readers and search engines. Displays when images fail to load and is critical for accessibility and image SEO.

Why It Matters

Alt text is mandatory for web accessibility compliance (ADA, WCAG) and a key image ranking factor. Images with descriptive alt text rank significantly higher in Google Images and help pages rank for keywords. Pages without alt text face accessibility lawsuits and miss image search opportunities.

How It Works

Alt text is added via the 'alt' attribute in HTML image tags. Screen readers read alt text aloud for visually impaired users, and search engines use it to understand image content and context. Well-written alt text improves both accessibility and SEO simultaneously.

Use Cases

  • An e-commerce product image uses alt='Black leather laptop bag with brass zipper 15-inch' instead of 'IMG_001.jpg'
  • A blog post image shows alt='Woman running on beach at sunrise wearing Nike running shoes' capturing relevant keywords naturally
  • A real estate site describes property photos with alt='Modern 3-bedroom house with backyard pool in Austin Texas' for local image SEO

Best Practices

  • Describe image content accurately and specifically in 125 characters or less
  • Include target keywords naturally when relevant to the image, but don't stuff keywords
  • Skip phrases like 'image of' or 'picture of' - screen readers already announce it's an image
  • Leave alt text empty (alt='') for decorative images that add no content value
  • Be specific: 'golden retriever puppy playing with red ball' not just 'dog'
  • Add alt text to all content images - it's required for accessibility compliance

Frequently Asked Questions

Why is Alt Text important? +
Alt text is mandatory for accessibility compliance (ADA, WCAG) and a key image ranking factor. It helps visually impaired users, makes images rank in Google Images, and prevents accessibility lawsuits.
How does Alt Text work? +
Alt text is added via the 'alt' attribute in HTML. Screen readers read it aloud for visually impaired users, search engines use it to understand image content, and it displays when images fail to load.
What makes good Alt Text? +
Good alt text accurately describes image content in 125 characters or less, includes keywords naturally when relevant, avoids phrases like 'image of', and is specific rather than generic. Focus on descriptive, useful content.

Related Terms

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