NTP Online TesterThis tool is useful to check if a given Network Time Protocol server is reachable over the internet using IPv4 and IPv6 connectivity.
It is also useful for knowing the resulting offset using the exact time of 1a.ncomputers.org stratum 2 NTP public server.
It uses linux command
ntpdate -q to perform a time synchronization query which also works for windows servers.
As an example you may check the status of 1b.ncomputers.org stratum 2 NTP public server.
Recommended for web hosting and server admins: How to join your linux server to the NTP pool project.