Image Alt Text.

Helps images appear in Google Image search — additional traffic source

What does this check test?

This check verifies that all `<img>` elements have `alt` attributes with descriptive, keyword-relevant text that accurately describes the image content. From an SEO perspective, alt text serves as the primary signal Google uses to understand image content for Google Image Search rankings. Alt text should be specific and descriptive (not just "image" or "photo"), naturally incorporate relevant keywords without stuffing, and be under 125 characters for optimal screen reader compatibility.

Why does it matter?

Google Image Search drives significant traffic — for some sites, image search can account for 20–30% of total organic traffic. Google cannot "see" images the way humans do; it relies primarily on alt text, surrounding text, and file names to understand image content. Images with good alt text appear in Google Image Search results, in Google's featured snippets with images, and in Google Discover. Missing alt text means missing traffic. This check overlaps with accessibility (WCAG 1.1.1) but focuses on the SEO value: keyword optimization, image search visibility, and featured snippet eligibility.

Who is affected?

Content authors uploading images to pages and blog posts, e-commerce teams managing product photography, marketing teams creating landing pages with hero images, and CMS developers building image upload workflows that prompt for alt text. SEO specialists should audit alt text quality during content reviews.

Where does this apply?

Every `<img>` element on the site: product images, blog post images, team photos, infographics, screenshots, diagrams, hero images, logos, and thumbnails. E-commerce product pages benefit most from optimized alt text. Decorative images (backgrounds, spacers, visual flourishes) should use empty alt (`alt=""`) to signal they have no informational content.

How to fix it

<!-- Bad: generic, no keywords -->
<img src="scan-results.png" alt="results">
<img src="shoes.jpg" alt="shoes">

<!-- Good: specific, includes relevant keywords -->
<img src="scan-results.png"
     alt="AppVet security scan results showing 3 critical vulnerabilities in HTTP headers">
<img src="shoes.jpg"
     alt="Blue running shoes Nike Air Max 270 side view">

<!-- Decorative: empty alt -->
<img src="divider.svg" alt="" role="presentation">

import Image from 'next/image';

<Image
  src={heroImg}
  alt="Web security scanner dashboard showing real-time vulnerability detection"
  width={1200}
  height={630}
/>

References

• Google — Google Image SEO best practices
• web.dev — Image elements have alt text
• Moz — Image SEO: Alt Text Best Practices