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Rustamjon Akhmedov
Rustamjon Akhmedov

Posted on • Originally published at altaudit.com

How to Check if an Image Has Alt Text: 4 Easy Methods

#wcag

Why Alt Text Matters

Alt text (alternative text) is a short written description added to an image via the alt attribute in HTML. It serves two critical purposes:

  1. It allows screen readers to describe images to visually impaired users
  2. It gives search engines context to understand what an image depicts

According to the WebAIM Million 2025 report, 95.9% of home pages have detectable WCAG failures, and missing alt text remains the single most common accessibility error found on the web.

Method 1: Inspect the Page Source (View Source)

The simplest way to check alt text is to view the raw HTML source:

  1. Open the page in your browser
  2. Right-click anywhere and select View Page Source (or press Ctrl+U / Cmd+U)
  3. Use Ctrl+F / Cmd+F to search for <img
  4. For each image tag, look for the alt attribute

Example of properly formatted alt text:

<img src="photo.jpg" alt="A woman reading a book in a library">
Enter fullscreen mode Exit fullscreen mode

If the alt attribute is missing entirely, or if it's present but empty (alt=""), the image may need attention. Note that alt="" is intentionally used for decorative images—this is valid per WCAG standards.

Method 2: Use Browser Developer Tools (Inspect Element)

For a faster, more visual approach:

  1. Right-click directly on the image you want to check
  2. Select Inspect or Inspect Element
  3. The DevTools panel will open with the image's HTML highlighted
  4. Look for the alt attribute in the highlighted <img> tag

This method is especially useful when you want to check a specific image quickly without searching through the full page source.

Method 3: Use the WAVE Accessibility Tool

The WAVE browser extension from WebAIM is one of the most widely used free accessibility testing tools available.

How it works:

  • Install the WAVE browser extension (Chrome or Firefox)
  • Navigate to the page you want to check
  • Click the WAVE extension icon
  • Red icon = missing alt text (critical error)
  • Green icon = alt text is present
  • Yellow icon = potential concern (suspiciously long, duplicated, or filename-based)

WAVE also displays a summary count of errors, making it easy to see how many images on a page are missing alt text.

Method 4: Use Alt Audit for Sitewide Checks

For larger websites with hundreds or thousands of images, automated tools like Alt Audit save hours of manual work:

  • Scan thousands of images across your entire domain in minutes
  • Identify exactly which pages and images are missing alt text
  • Get AI-powered suggestions to generate descriptive alt text automatically
  • Track your progress over time as you fix issues

What Makes Good Alt Text?

Follow these guidelines when writing alt descriptions:

✓ Be descriptive and specific: "Golden retriever puppy playing in autumn leaves" beats "dog"
✓ Keep it concise: Aim for under 125 characters (screen readers may cut off longer text)
✓ Don't start with "Image of" or "Photo of": Screen readers already announce it's an image
✓ Reflect context: The same image might need different alt text depending on where it appears
✓ Use empty alt for decorative images: alt="" tells screen readers to skip purely decorative images

Common Alt Text Mistakes to Avoid

Watch out for these frequent errors:

✗ Missing alt attribute entirely
✗ Using filenames as alt text ("IMG_4823.jpg")
✗ Keyword stuffing ("best cheap shoes buy shoes online")
✗ Identical alt text on different images
✗ Alt text that's too long or too short to be meaningful

Quick Comparison: All 4 Methods

Method Best For Scope Cost Skill Level
View Source Quick spot-checks Single page Free Beginner
DevTools Inspecting specific images Single element Free Intermediate
WAVE Extension Visual accessibility overview Single page Free Beginner
Alt Audit Full site audits at scale Entire domain Free tier available Beginner

Final Thoughts

Whether you're a developer, content manager, or SEO specialist, knowing how to check if an image has alt text is fundamental for building accessible, high-performing websites. For fast, thorough, and scalable solutions, automated tools like Alt Audit help you stay compliant with WCAG standards while improving your site's accessibility and search rankings.

Canonical URL: https://altaudit.com/blog/how-to-check-if-image-has-alt-text

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