Date/Time Format Codes

This is a summary of standard date/time codes that may be used in format strings:

Valid format codes for custom subfolders

%a

The abbreviated weekday name according to the current locale.

%A

The full weekday name according to the current locale.

%b

The abbreviated month name according to the current locale.

%B

The full month name according to the current locale.

%c

The preferred date and time representation for the current locale.

%C

The century number (year/100) as a 2-digit integer.

%d

The day of the month as a decimal number (range 01 to 31).

%D

Equivalent to %m/%d/%y. (Yecch -- for Americans only. Americans should note that in other countries %d/%m/%y is rather common. This means that in international context this format is ambiguous and should not be used.)

%e

Like %d, the day of the month as a decimal number, but a leading zero is replaced by a space.

%E

Modifier: use alternative format, see below.

%F

Equivalent to %Y-%m-%d (the ISO 8601 date format). (C99)

%G

The ISO 8601 year with century as a decimal number. The 4-digit year corresponding to the ISO week number (see %V). This has the same format and value as %y, except that if the ISO week number belongs to the previous or next year, that year is used instead.

%g

Like %G, but without century, i.e., with a 2-digit year (00-99).

%h

Equivalent to %b.

%H

The hour as a decimal number using a 24-hour clock (range 00 to 23).

%I

The hour as a decimal number using a 12-hour clock (range 01 to 12).

%j

The day of the year as a decimal number (range 001 to 366).

%k

The hour (24-hour clock) as a decimal number (range 0 to 23); single digits are preceded by a blank. (See also %H.)

%l

The hour (12-hour clock) as a decimal number (range 1 to 12); single digits are preceded by a blank. (See also %I.)

%m

The month as a decimal number (range 01 to 12).

%M

The minute as a decimal number (range 00 to 59).

%O

Modifier: use alternative format, see below.

%p

Either 'AM' or 'PM' according to the given time value, or the corresponding strings for the current locale. Noon is treated as 'pm' and midnight as 'am'.

%P

Like %p but in lowercase: 'am' or 'pm' or a corresponding string for the current locale.

%r

The time in a.m. or p.m. notation. In the POSIX locale this is equivalent to '%I:%M:%S %p'.

%R

The time in 24-hour notation (%H:%M). For a version including the seconds, see %T below.

%s

The number of seconds since the Epoch, i.e., since 1970-01-01 00:00:00 UTC.

%S

The second as a decimal number (range 00 to 60). (The range is up to 60 to allow for occasional leap seconds.)

%T

The time in 24-hour notation (%H:%M:%S).

%u

The day of the week as a decimal number, range 1 to 7, Monday being 1. See also %w.

%U

The week number of the current year as a decimal number, range 00 to 53, starting with the first Sunday as the first day of week 01. See also %V and %W.

%V

The ISO 8601:1988 week number of the current year as a decimal number, range 01 to 53, where week 1 is the first week that has at least 4 days in the current year, and with Monday as the first day of the week. See also %U and %W.

%w

The day of the week as a decimal, range 0 to 6, Sunday being 0. See also %u.

%W

The week number of the current year as a decimal number, range 00 to 53, starting with the first Monday as the first day of week 01.

%x

The preferred date representation for the current locale without the time.

%X

The preferred time representation for the current locale without the date.

%y

The year as a decimal number without a century (range 00 to 99).

%Y

The year as a decimal number including the century.

%z

The time-zone as hour offset from GMT. Required to emit RFC 822-conformant dates (using "%a, %d %b %Y %H:%M:%S %z").

%Z

The time zone or name or abbreviation.

Some conversion specifications can be modified by preceding the conversion specifier character by the E or O modifier to indicate that an alternative format should be used. If the alternative format or specification does not exist for the current locale, the behaviour will be as if the unmodified conversion specification were used. The Single Unix Specification mentions %Ec, %EC, %Ex, %EX, %Ey, %EY, %Od, %Oe, %OH, %OI, %Om, %OM, %OS, %Ou, %OU, %OV, %Ow, %OW, %Oy, where the effect of the O modifier is to use alternative numeric symbols (say, roman numerals), and that of the E modifier is to use a locale-dependent alternative representation.