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Measure HTTP load times and TTFB with curl

harmlessNetworkalle
Adjust the values, the command updates live
user@server
curl -o /dev/null -sS -w 'DNS: %{time_namelookup}s  Connect: %{time_connect}s  TLS: %{time_appconnect}s  TTFB: %{time_starttransfer}s  Gesamt: %{time_total}s\n' https://example.com/

Loads the page, discards the content and prints the cumulative timestamps of the individual phases. A high TTFB with a fast TLS handshake points to slow PHP or a slow database. A high DNS time, on the other hand, indicates a name resolution problem.

Note: The values are cumulative, each value includes the previous phases.

Also searched as

  • measure ttfb with curl
  • curl timing breakdown
  • why is my website slow time to first byte

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