Is Unix Time Universal?
Contents Is Unix Time the Same Everywhere? the Unix Timestamp Is the Number of Seconds (Or Milliseconds) Elapsed Since an Absolute Point in Time, Midnight of...
Is Unix time the same everywhere?
The UNIX timestamp is the number of seconds (or milliseconds) elapsed since an absolute point in time, midnight of Jan 1 1970 in UTC time. (UTC is Greenwich Mean Time without Daylight Savings time adjustments.) Regardless of your time zone, the UNIX timestamp represents a moment that is the same everywhere.
Is Unix time accurate?
Probably not, since computer clock time tends to be rather arbitrary. However, if you control all of those computers and can ensure that it is synchronized using NTP or some such service, you might be able to sync all of those actions even using Javascript.