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Speed Test

Measure response time and page size for any URL.

Page speed directly impacts user experience and search rankings. Google's Core Web Vitals — LCP (loading speed), FID (interactivity), and CLS (visual stability) — are ranking factors. Studies show a 1-second delay can reduce conversions by up to 7%.

Common bottlenecks include unoptimized images, excessive JavaScript blocking the main thread, slow server processing, and missing cache headers that force browsers to re-download static assets on every visit.

This tool measures DNS resolution, Time to First Byte (TTFB), total load time, and page size — helping you identify exactly where to optimize.

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Common questions

Time to First Byte is how long until the server starts sending the response body. High TTFB often points to slow origin compute, cold caches, or distant servers.

No. We measure server-side fetch timing and size from our probe. Lab tools like Lighthouse estimate browser rendering metrics separately.

Network congestion, CDN cache state, and origin load change over time. Compare several runs and trends, not a single sample.

What the speed test measures

This tool loads your URL from our server and reports DNS resolution time, Time to First Byte (TTFB), total load time, response status code, and downloaded page size. The rating (Fast, Moderate, Slow) gives a quick benchmark — useful for comparing before/after optimization or checking a site from an external network outside your office.

When to run a speed test

  • After deploying performance optimizations (image compression, caching, CDN)
  • When users in other regions report slowness
  • Before and after migrating hosting providers
  • Validating that a staging environment matches production performance
  • Establishing a baseline for Core Web Vitals improvement work

How to read the metrics

DNS — high values suggest slow or distant nameservers; consider a faster DNS provider. TTFB — time until the server starts sending the response; high TTFB usually means slow backend, database queries, or missing caching. Total — full download time including HTML; large pages or slow third-party scripts inflate this. Size — uncompressed or poorly optimized pages exceed 1–2 MB quickly on mobile networks.

Google uses Core Web Vitals (LCP, INP, CLS) for ranking — TTFB correlates with LCP on many sites. Aim for TTFB under 200ms on cached pages and under 800ms on dynamic content.

Common bottlenecks

  • Unoptimized hero images served at full resolution
  • Render-blocking JavaScript in the document head
  • No CDN for static assets
  • Database queries on every page view without object caching
  • Shared hosting oversubscription during peak hours

Example scenario

A WordPress blog showed 4.2s TTFB. Investigation revealed a misconfigured plugin running remote API calls on every page load. Disabling the plugin dropped TTFB to 180ms — the speed test made the regression obvious immediately after a plugin update.

Limitations

Tests run from our infrastructure location, not from every country. Results vary by time of day and network conditions. This is not a full Lighthouse audit — it measures server/network timing, not client-side JavaScript execution or layout shifts.

Related resources

Understanding HTTP/3 · Header Inspector · Website Health Check · Post-Migration Checklist