How Scans Work
What happens behind the scenes when you scan a URL with usability.cat.
When you paste a URL into usability.cat, here's what happens:
The scan process
1. We visit your site twice
We load your page on both desktop and mobile screen sizes using a real browser. This catches responsive design issues that only show up on phones.
2. We capture everything
For each visit, we grab:
- A full screenshot of the page
- The complete HTML structure
- All CSS styles being applied
- JavaScript files loaded by the page
3. AI analyzes your page
Our AI examines your page across multiple categories:
- Visual design — layout, typography, colors, spacing
- Accessibility — contrast ratios, semantic HTML, keyboard navigation
- Security — headers, vulnerable patterns, exposed data
- Performance indicators — resource loading, JavaScript bundles
4. You get a report
The results come back as a paw rating (1-5 paws) with specific issues broken down by category. Each issue includes:
- What the problem is (in plain English)
- Why it matters
- How to fix it (with a prompt you can paste into your AI tool)
How long does a scan take?
Most scans complete in 30-60 seconds. Complex pages with lots of JavaScript may take a bit longer.
What counts as one scan?
One URL = one scan = one life. If you want to scan your homepage and your settings page, that's two lives.