Free Page Size Checker

Page weight is a ranking factor in disguise — heavy HTML slows rendering and burns crawl budget. NToolHub's free Page Size Checker weighs your HTML and runs a real gzip compression pass (via CompressionStream) to show true transfer size. Performance-minded SEOs use it to catch bloated templates.

Tip: right-click a page → “View page source”, copy it, and paste it here. Nothing leaves your browser.
Private by design. This tool runs 100% in your browser — your content is never uploaded to any server.

How to Use the Page Size Checker

  1. Paste the page HTML and click Measure Size.
  2. Read the raw vs gzipped transfer size — gzip is what users download.
  3. Aim for under 100 KB transferred for the HTML document.
  4. Minify markup, move scripts to external files and defer non-critical JS.

Features

Paste HTML for byte-accurate raw size plus a genuine in-browser gzip estimate with compression ratio, performance verdicts at 100KB/300KB thresholds, and guidance on what the measurement covers versus external assets.

Benefits & Use Cases

Lighter pages render faster, score better on Core Web Vitals (LCP), and let Google crawl more of your site per visit. Knowing your true transfer size — not just raw bytes — is what actually affects users.

Tips

Aim for under 100KB transferred for the HTML document, minify markup, move inline scripts and styles to external deferred files, and audit images/fonts separately in DevTools — they usually dwarf the HTML.

Frequently Asked Questions

Why show gzipped size instead of raw size?

Servers compress HTML with gzip/brotli before sending it — the compressed size is what users actually download. A 300KB document might transfer as just 40KB.

Is the gzip estimate accurate?

Yes — the tool runs a real gzip compression pass in your browser via CompressionStream, not a rough ratio guess. Results match server gzip closely.

What's a good HTML page weight?

Under 100KB transferred is excellent; under 300KB is acceptable. Beyond that, minify, defer scripts and split content.

Does this include images and scripts?

No — it measures the HTML document only. Images, fonts and JS bundles are separate requests; audit those in your browser's DevTools Network panel.

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