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Alt Text Checker

Scan HTML for all img elements and evaluate their alt text. Flags missing alt attributes, empty alt text (which may be intentional for decorative images but is often an error), filename-based alt text, and overly long descriptions. Provides WCAG 1.1.1 compliance guidance.

Why This Matters

Missing alt text is the single most common WCAG violation. Screen readers skip images without alt attributes entirely, leaving users unaware of important content. WCAG 1.1.1 requires text alternatives for all non-text content. Even decorative images need an explicit empty alt (alt="") to indicate they should be skipped.

How to Use This Tool

  1. 1

    Paste HTML

    Paste your HTML containing <img> elements into the textarea.

  2. 2

    Review findings

    The tool flags missing alt, empty alt, filename-based alt, and overly long descriptions.

  3. 3

    Fix and re-check

    Add or improve alt text and paste again to verify.

Frequently Asked Questions

When should alt text be empty?

Use empty alt (alt="") only for purely decorative images that convey no information — spacer GIFs, decorative borders, background-style images. Screen readers will skip these. If the image conveys any meaning, it needs descriptive alt text.

How long should alt text be?

Aim for 100-125 characters. Focus on the purpose and content of the image in context. For complex images like charts, consider a longer description in the surrounding text or a details element.

Should I use 'Image of' or 'Picture of'?

No. Screen readers already announce 'image' before the alt text. Starting with 'Image of' is redundant. Describe what the image shows directly, e.g., 'A customer using the mobile app' not 'Image of a customer using the mobile app'.

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