AltCatch isn't appearing on this page.

Chrome doesn't let any extension run on chrome:// URLs, the Chrome Web Store, or some PDF viewers. Try AltCatch on a normal https:// page.

My audit history disappeared.

AltCatch stores history in chrome.storage.local on your device only. Clearing Chrome's site data, uninstalling, or running a fresh profile will wipe it. Nothing is cloud-synced.

Can I audit a whole site at once?

Not yet. v1 is page-by-page on demand. Sitemap-driven full-site auditing is on the roadmap — still 100% in your browser, no servers.

How do I report a bug?

Email hello@mhtawfik.com with the URL, a screenshot, and the AltCatch version (find it in chrome://extensions).

AltCatch — Find Missing Alt Text & Broken Links

Audit any web page for missing alt text and broken images in seconds — then export the report as clean Markdown.

Install on Chrome Web Store View privacy policy

https://example.com/about

AltCatch

example.com/about

12 images

2 critical1 warning1 decorative

Missing altNo alt attribute
<img src="hero-photo.jpg">
Broken imageHEAD 404
<img src="/logo-old.png" alt="Company logo">
Placeholder altLazy filler text
<img alt="image" src="banner.png">
DecorativeIntentional empty alt
<img alt="" src="divider.svg">

Export MarkdownCopy

What AltCatch catches

Five severity classes, ranked by impact. Critical issues fail WCAG 2.2; warnings break accessibility in practice; decorative entries are shown for context.

Missing alt

Critical

Images with no alt attribute at all. A WCAG 2.2 failure.

Broken images

Critical

404s and load failures, verified with lightweight HEAD requests.

Placeholder alt

Warning

Lazy alt text like "image", "untitled", or the raw filename.

Whitespace-only alt

Warning

Alt attributes that contain only spaces. Screen readers skip them.

Decorative alt=""

Info

Intentionally empty alt for decorative images. Shown collapsed, for context.

How it works

On-demand. Page-by-page. Everything runs locally in your browser.

1
Click the AltCatch icon or open the side panel on any page.
2
AltCatch scans every <img> in the DOM and resolves its real source.
3
Broken images are verified asynchronously — no heavy downloads of the actual files.
4
Results stream into a grouped checklist with a live health breakdown.
5
Export to Markdown or copy to clipboard. Done.

Built for

Anyone who has to ship pages that pass an accessibility review or rank in image search.

Web developers

shipping accessible HTML

SEO specialists

auditing image SEO and image search visibility

Accessibility auditors

documenting WCAG 2.2 compliance

QA testers

writing reproducible bug tickets

Why AltCatch

Other tools spot the same images. AltCatch turns them into a deliverable.

Markdown export

Markdown export drops straight into GitHub, Linear, Notion, or PR descriptions — no reformatting.

Five-tier severity classification

Severity classification beyond "missing alt" — catches lazy, placeholder, and decorative cases other tools miss.

Audit history

Audit history so you can track progress across pages and re-check after a fix.

Zero signup, zero servers

No account, no signup, no upload. Open it and audit.

AltCatch runs 100% locally. No data ever leaves your browser.

Read the full privacy policy

What's next

AltCatch ships today with on-demand, page-by-page auditing — the foundation for full-site, sitemap-driven auditing in a future release. Every audit you run now carries forward into your history.