TTFB Checker
Measure Time to First Byte — how quickly a server starts responding, once the connection is already open.
About this tool — TTFB is not page load time
Time to First Byte is specifically the delay between the connection being ready and the server sending the very first byte of its response — essentially, how long the server took to start generating the page. It is not the same as full page load time, which also includes downloading the complete response, then every linked resource (CSS, JS, images), then the browser parsing and rendering all of it. TTFB isolates server-side responsiveness from everything that happens afterward in the browser.
Why TTFB is a useful signal on its own
A slow TTFB usually points to server-side causes — slow backend processing, database queries, or server load — rather than front-end asset weight. A fast TTFB with a slow overall page load instead points toward the front-end (too many or too-large assets), which is a completely different problem to fix.
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