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date

date prints the current date and time. With the right option, it can also set the system clock, display some other moment, or format a date however you need.

date [options] [+format]

$ date
Sun 17 May 2026 14:32:08 BST
$ date +%Y-%m-%d
2026-05-17

Formatting the output

A +format argument controls the output. The format string is printed literally, except for % sequences, each of which is replaced by a piece of the date. The common ones:

Sequence Is replaced by
%Y %m %d Year, month, day.
%H %M %S Hour, minute, second.
%F The full date — same as %Y-%m-%d.
%T The time — same as %H:%M:%S.
%A %a Weekday name, full and abbreviated.
%B %b Month name, full and abbreviated.
%j Day of the year.
%s Seconds since 1970-01-01 UTC.
%z %Z Numeric and named time zone.
%% A literal %.

The full set is long; date --help lists every sequence with an example.

Displaying a different moment

Option Effect
-d, --date=STRING Show the time described by STRING — "yesterday", "next Friday", "@1615432800" — instead of now.
-r, --reference=FILE Show FILE's last modification time.
-f, --file=DATEFILE Like -d, but once for each line of DATEFILE.
-u, --universal Work in Coordinated Universal Time (UTC) rather than the local zone.

Standard formats

Option Output
-I, --iso-8601[=FMT] ISO 8601 — FMT is date, hours, minutes, seconds, or ns.
-R, --rfc-email The format used in email headers.
--rfc-3339=FMT RFC 3339 — FMT is date, seconds, or ns.

Setting the clock

Option Effect
-s, --set=STRING Set the system clock to the time described by STRING.

Setting the clock changes state for the whole system, so it is a privileged operation — it succeeds only for a caller whose token carries the right to set the time, and is refused otherwise. See Privileges.

Exit status

Code Meaning
0 The date was printed or set.
1 An invalid date or format, or the clock could not be set.

See also