Page Speed Checker

Measures the real network timings of the request — DNS, TCP, TLS, time-to-first-byte, and total download — using Node’s low-level socket events for sub-millisecond accuracy. Then probes the top scripts, stylesheets and images for size. Server-side measurement, so it doesn’t depend on your browser.

What This Tool Measures (and What It Can’t)

This tool uses Node’s low-level socket events to give you the real network timings of your page request: DNS resolution, TCP connect, TLS handshake, time-to-first-byte (TTFB), and total HTML download. These numbers are what your origin server is actually responsible for — they don’t depend on your browser, plugins, or device.

What this tool does NOT measure

Core Web Vitals (LCP, CLS, INP), JavaScript execution time, render-blocking CSS, layout shifts, third-party tag impact, and anything about the visual rendering of the page. Those require a real browser. Use Google PageSpeed Insights, WebPageTest, or Chrome DevTools’ Performance panel for that.

How to use the numbers

  • TTFB > 600 ms almost always points at the origin (slow database queries, cold serverless starts, lack of edge caching).
  • TLS > 500 ms indicates older TLS configuration — TLS 1.3 plus session resumption can shave 100–300 ms.
  • DNS > 300 ms means your DNS provider is slow or you’re not using anycast.
  • Total page bytes > 3 MB is a budget-buster on mobile; investigate images, fonts, and JavaScript first.