Website speed / TTFB
Measure time to first byte and total response time.
This website speed test measures how quickly a page responds, with particular focus on time to first byte — the delay before the server returns the first byte of the response. It separates the time spent waiting on the server from the total transfer time, so you can see whether slowness comes from the backend or from page weight. A low TTFB points to a responsive server. Because performance degrades gradually as traffic and content grow, it's worth tracking over time.
Frequently asked questions
What is TTFB and why does it matter?
Time to first byte measures the gap between the request and the first byte of the server's response, reflecting backend and network speed. A high TTFB delays everything that follows and hurts perceived performance.
What's a good TTFB value?
Under roughly 200 milliseconds is excellent, while consistently high values point to slow backend processing, database queries, or network distance.
Why does the number vary between runs?
Caching, server load, and network conditions all move TTFB run to run. A single measurement is a snapshot; continuous monitoring shows the real trend.
Is TTFB the same as page load time?
No. TTFB is just the server's first response; full page load also depends on assets, scripts, and rendering. TTFB is the foundation everything else builds on.
Can slowdowns be detected automatically?
Yes. SJ Monitor's response-time monitoring measures your timings continuously and alerts you when response time degrades beyond your threshold.
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