Crawl Log
[18:21:45] System initialized. Quota: 3/3. Awaiting trigger.

The Sniffer On-Page SEO Auditor

On-page SEO audit

Enter a target URL above and press Execute Audit. The crawler fetches the page HTML, follows same-domain links up to the depth you selected, and reports six measurements per page. It respects robots.txt, blocks private and internal network ranges, verifies TLS certificates, and caps each response at 2 MB.

What each page reports

  • Page title length. Below 40 characters is Short. Above 60 characters is Long. Between 40 and 60 is Optimal.
  • Meta description length. Below 120 characters is Short. Above 160 characters is Truncated. Between 120 and 160 is Optimal.
  • H1 heading presence and text.
  • Body word count using Unicode word boundaries.
  • Number of image elements without a non-empty alt attribute.
  • Robots.txt compliance. Allow and Disallow rules are parsed. The longest matching rule wins.

Scope and limits

This is a single-file PHP crawler that audits the HTML returned by the server. It does not execute JavaScript, so pages rendered entirely in the browser may return empty or partial content. It does not measure Core Web Vitals, backlinks, keyword rankings, accessibility compliance, or rendered layout. Results reflect the response at the time of the run and are not stored between sessions.

How to run an audit

  1. Enter a full URL including https:// in the Target Website Domain / URL field.
  2. Set the Depth Limit to the number of pages to audit between 1 and 20.
  3. Press Execute Audit. Progress streams into the Execution Log panel.
  4. Review the KPI summary and the per-page table. Use Export CSV to download the report.

Rate limit

Each client IP may run up to 3 audits per calendar day. The remaining quota for this session appears in the Execution Log on load.

Security and privacy

Requests to private, loopback, link-local, and cloud metadata IP ranges are blocked at both the constructor and the fetch layer. DNS resolution is pinned per request to prevent rebinding. TLS certificates are verified. Responses larger than 2 MB are rejected. Exported CSV values that could be read as spreadsheet formulas are prefixed to neutralize them.

Frequently Asked Questions

Does the audit execute JavaScript?

No. The crawler reads the raw HTML returned by the server. Pages rendered entirely in the browser may return empty or partial content.

Does the audit respect robots.txt?

Yes. Allow and Disallow directives are parsed, longest-match precedence is applied, and disallowed URLs are skipped.

What User-Agent does the crawler send?

SnifferBot/1.0 is sent on every request.

What does the audit not measure?

Core Web Vitals, backlinks, keyword rankings, accessibility compliance, and browser-rendered content are not measured. This is a crawl-time HTML audit only.