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bashunix-timestamp

Commandline to convert ISO8601 time to unix timestamp

What is the most efficient way to get a unix timestamp for a given ISO 8601 date and vice versa?

There are several third party websites to do this. However I am looking for a simple command that can be executed at the Linux prompt

Solution

  • Convert ISO Date/Time to Unix timestamp

    date -d 'date' +"%s"

    Example

       bash-# date -d 'Fri Dec  8 00:12:50 UTC 2017' +"%s"
   bash-# 1512691970

    man -a date

       -d, --date=STRING
          display time described by STRING, not 'now'

   %s     seconds since 1970-01-01 00:00:00 UTC

    Convert Unix timestamp to ISO Date/Time

    date -Iseconds -d @<unix timestamp>

    Example

       bash-# date -Iseconds -d @1512711426
   bash-# 2017-12-07T21:37:06-0800

    man -a date

       -d, --date=STRING
          display time described by STRING, not 'now'


   -I[TIMESPEC], --iso-8601[=TIMESPEC]
          output  date/time  in  ISO 8601 format.  
          TIMESPEC='date' for date only (the default), 'hours',                             
          'minutes', 'seconds', or 'ns' for date and time to the 
          indicated precision.