But as we now know, all time-related information in the Zabbix database is stored as Unix timestamps. For that, the GNU date command can help again. Execute the following on the Zabbix server, by replacing the exact time with what you deduced from the latest values:

$ date -d "2016-03-13 13:13:13" "+%s"

That'll output the Unix timestamp of that moment, which in the case of this example would be 1457867593.

Be aware of the difference in time zones, though—values displayed in the frontend will usually have the local time zone applied. Check that the value for the timestamp you obtained matches the value in the database for that same timestamp. There's actually an easier and safer way to obtain the value timestamp. While still looking at the value history for the item in the frontend, click the As plain text button in the upper-right corner:

Notice how the third column is exactly what we wanted—the Unix timestamp. In this case, we don't have to worry about the time zone, either.