Command:
curl -kv -w '\n* Response time: %{time_total}s\n' <IP_OR_URL>
Example:
curl -kv -w '\n* Response time: %{time_total}s\n' https://google.com
Definition of time_total
according to the docs:
The total time in seconds, that the full operation lasted. The time will be displayed with millisecond resolution.
References: