Page Source Viewer
Fetch any URL server-side and view its raw HTML source, syntax-highlighted — no browser CORS restrictions, and an optional Googlebot user agent to spot content that's cloaked from search crawlers.
Input
The page is fetched server-side and its raw HTML response is returned as-is.
Some sites serve different HTML to crawlers than to browsers — switch this to check.
Output
Response
| Field | Value |
|---|---|
| No data yet | |
Guides
What the Page Source Viewer does
Enter a URL and this tool fetches the page server-side and returns its raw, unrendered HTML — the same document a browser downloads before it runs any JavaScript or applies any CSS. It's the equivalent of "View Page Source" for a URL you don't control, without the cross-origin restrictions that block a browser tab from reading another site's response directly.
How to use it
- Enter the full URL of the page you want to inspect.
- Optionally switch Fetch as to Googlebot or Bingbot instead of a standard browser.
- Click View source. The page is fetched server-side and its HTML is returned, syntax-highlighted and ready to copy or download.
Why fetch as a crawler?
Most sites serve byte-identical HTML no matter who's asking, but some deliberately (or accidentally) return different content to search bots than to real visitors — a technique called cloaking, and one Google explicitly penalizes. Switching Fetch as to Googlebot or Bingbot lets you spot-check whether a page's crawler-facing HTML actually matches what a browser sees, without needing to change your own browser's user agent.
What this doesn't do
This reads the raw HTTP response only — it doesn't execute JavaScript, so content injected client-side after the page loads won't appear here. For a deeper mobile-vs-desktop crawler comparison, see the Mobile-First Index Checker; for a locale/geo-based cloaking check instead of a user-agent one, see the Locale Cloaking Checker.
Privacy
The URL is fetched by our server only to return its HTML and isn't stored. Requests to private or local network addresses are blocked.
Use it from code
From 3 credits per callREST API
curl -X POST https://api.iotools.cloud/v1/tool/page-source-viewer \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"url": "https://example.com",
"userAgent": "browser"
}'Swap in your own key from your account. The tool's fields are the body — no wrapper.
Ask an AI agent
Use the IOTools `page-source-viewer` tool (Page Source Viewer) on this input:
YOUR_INPUT_HEREPaste this at any agent connected to the IOTools MCP server, then add your input.