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Ubify Core Engineering Team
SOFTWARE ENGINEERS & SYSTEMS ARCHITECTS
About This Tool
The page size checker retrieves the raw HTML document payload of any public web page and reports its document weight in bytes and kilobytes. Measuring the initial markup payload is an essential first step when auditing server response budgets, Time to First Byte (TTFB), and mobile network delivery latency.
### Document Size Calculation
When you test a domain or URL: 1. The URL is normalized to include standard protocol prefixes (`https://`). 2. The raw HTML response string is retrieved using an ephemeral CORS proxy gateway. 3. Document weight is measured using JavaScript Blob byte calculation: `new Blob([contents]).size`. 4. The result displays the exact size in bytes alongside a converted kilobyte metric (bytes divided by 1,024).
### Tested Scenario Example
Testing a lightweight documentation landing page: - Target URL: `https://example.com` - Retrieved HTML string: 1,256 bytes. - Displayed Size: **1.23 KB (1,256 bytes)**. - Diagnostic: Extremely lean base document requiring minimal TCP packets to deliver initial layout content.
### Network Processing & Scope Disclaimer
This tool routes your requested public target URL through a temporary CORS proxy server solely to retrieve the initial HTML markup document. It does NOT download external linked assets (such as CSS stylesheets, JavaScript bundles, video files, or raster images) and does not execute client-side scripts. For comprehensive total waterfall weight including all subresources, inspect the Chrome DevTools Network tab.
How to Use
- 1
Type or paste a complete public URL (e.g., https://example.com) into the address input box.
- 2
Click the "Check Size" action button to trigger the document fetch.
- 3
Examine the resulting summary card displaying total HTML size in kilobytes and bytes.
- 4
Review document transfer efficiency to evaluate initial markup weight against web performance budgets.
Frequently Asked Questions
Does this size measurement include images, stylesheets, and JavaScript files?
No. This scanner measures the transferred size of the root HTML markup document itself. It does not cascade through external subresources or execute embedded scripts.
Can this tool scan pages protected behind a login or private intranet?
No. The proxy scanner can only reach publicly accessible HTTP and HTTPS URLs. Internal development servers and password-gated dashboards cannot be reached.
How does the tool fetch remote web pages without browser CORS restrictions?
Browser cross-origin security prevents client scripts from directly fetching third-party domains. The request is routed through a temporary proxy service that relays public HTML content back to your browser session.