Image Alt Text Checker

Audit every <img> tag on any webpage. Detect missing, empty, and generic alt text, check for missing dimensions, and get a detailed score with actionable fix suggestions.

Check Image Alt Text

Enter any webpage URL. The tool will fetch and analyze all <img> tags for alt text quality, dimensions, and lazy loading status.
Quick test:

About the Image Alt Text Checker

This tool fetches any webpage and performs a comprehensive image audit. It checks every <img> tag for:

Missing alt attributes

Images without any alt attribute are invisible to screen readers and get the filename read instead — always an accessibility fail.

Empty
Empty alt text

Identifies alt="" attributes, which are valid and intentional for decorative images that don't convey content.

Generic alt text

Flags alt text like "image", "photo", or "logo" that doesn't describe the actual content — a missed SEO opportunity.

Why Alt Text Matters for SEO

Image alt text (alternative text) is one of the most commonly overlooked SEO and accessibility elements. Here's why it matters:

  • Search engine understanding — Search engines cannot "see" images; alt text is how they understand what an image shows. Descriptive alt text helps your images rank in Google Image Search, which can drive significant referral traffic.
  • Accessibility compliance — Millions of visually impaired users rely on screen readers that read alt text aloud. Missing or generic alt text makes your site inaccessible. Many countries have legal requirements for web accessibility (ADA, WCAG, EAA).
  • Core Web Vitals — Missing width/height attributes on images cause layout shifts (high CLS scores), which Google uses as a ranking factor. Adding dimensions is a quick fix that improves both UX and SEO.
  • Contextual relevance — Alt text helps search engines connect images to page content. An image of a "red mountain bike" surrounded by text about "best mountain bikes under $1000" reinforces your page's topical relevance.
  • Failure fallback — When images fail to load (slow connections, CDN issues), the alt text is displayed instead. Without it, users see an empty broken image icon.

Alt Text Best Practices

  • Every image needs an alt attribute — Even if empty for decorative images (alt=""). A missing alt attribute is an accessibility failure.
  • Be descriptive, not generic — Describe what the image shows: "Golden retriever puppy sitting in a garden with flowers" not "dog" or "photo".
  • Include keywords naturally — Incorporate relevant keywords where they fit naturally, but do not keyword-stuff. Write for humans first.
  • Keep it concise — 125 characters or fewer. Screen readers cut off longer text.
  • Empty alt for decorative images — Use alt="" for spacer GIFs, decorative borders, background ornaments, or purely visual elements.
  • Add explicit dimensions — Always include width and height attributes to prevent layout shifts.
  • Use lazy loading strategically — Use loading="lazy" for below-the-fold images, loading="eager" or omit for above-the-fold (hero) images.
  • Avoid "image of" / "picture of" — Screen readers already announce "image" before reading alt text. Starting with "image of" or "picture of" is redundant.

Frequently Asked Questions

Alt text helps search engines understand image content, improves accessibility for visually impaired users, and appears when images fail to load. Images with descriptive alt text can also rank in Google Image Search, driving additional organic traffic.
Generic alt text uses vague words like "image", "photo", "picture", or "logo" without describing the actual content. Search engines prefer specific, descriptive alt text because it provides actual context about the image subject. Generic alt text is a missed opportunity for both SEO and accessibility.
Decorative images should use an empty alt attribute (alt="") rather than no alt attribute. This tells screen readers to skip the image intentionally. A missing alt attribute is a different thing from an empty one — the former is an accessibility error, the latter is an intentional best practice for decorative elements. Always use alt="" for spacer images, background ornaments, and purely visual flourishes.
The general recommendation is 125 characters or fewer. Screen readers typically cut off alt text around 125 characters, so keeping your description concise while still conveying the image content is optimal. Focus on the key information the image conveys — what it shows and why it matters in context.
Yes — missing width and height attributes can negatively impact Core Web Vitals, specifically Cumulative Layout Shift (CLS). When images lack explicit dimensions, the browser reserves no space for them, causing the page layout to shift as images load. This creates a poor user experience and can hurt your page's SEO performance.
Lazy loading (loading="lazy") defers off-screen images to improve initial page load speed. It is recommended for below-the-fold images but should not be used on above-the-fold images (use loading="eager" or omit it for hero images). Proper lazy loading improves Largest Contentful Paint (LCP) and overall page experience signals.
A missing alt attribute means the &lt;img&gt; tag has no alt attribute at all — screen readers will read the image filename instead, which is usually meaningless. An empty alt attribute (alt="") is valid and tells screen readers to intentionally skip the image (correct for decorative images). Both are reported by this tool but only missing alt is a definite error requiring action.
Yes, alt text should include relevant keywords naturally, but avoid keyword stuffing. Describe what the image shows while incorporating relevant terms. For example, instead of "photo" use "blue mountain bike on a forest trail in Colorado". This helps both search engines understand context and users relying on screen readers.
No. We do not permanently store any URLs or results. Every check is processed in real-time and no data is saved to any database. Your privacy is fully protected.