Ruby Date Format (strftime)

Date Formatting

Format	Description
%Y	Year with century (e.g. 2015, 1995, etc)
%m	Month of the year, zero-padded (01..12)
%B	The full month name (e.g. January)
%b	The abbreviated month name (e.g. Jan)
%d	Day of the month, zero-padded (01..31)
%j	Day of the year (001..366)
%C	Year / 100 (round down, e.g. 20 in 2015)
%y	Year % 100 (00…99)
%_m	Month of the year, blank-padded (_1..12)
%-m	Month of the year, no-padding (1..12)
%^B	The full month name uppercased (e.g. JANUARY)
%^b	The abbreviated month name uppercased (e.g. JAN)
%h	Equivalent to %b (abbreviated month name)
%-d	Day of the month, no-padding (1..31)
%e	Day of the month, blank-padded (_1..31)

Flags

Flag	Description
-	Don’t pad a numerical output
_	Use spaces for padding
0	Use zeros for padding
^	Upcase the result string
#	Change case
:	Use colons for %z

Time Formatting

Format	Description
%H	Hour of the day, 24-hour clock, zero-padded (00..23)
%k	Hour of the day, 24-hour clock, blank-padded (_0..23)
%I	Hour of the day, 12-hour clock, zero-padded (01..12)
%l	Hour of the day, 12-hour clock, blank-padded (_1..12)
%P	Meridian indicator, lowercase (am or pm)
%p	Meridian indicator, uppercase (AM or PM)
%M	Minute of the hour (00..59)
%S	Second of the minute (00..59)
%L	Millisecond of the second (000..999)
%N	Nanosecond (9 digits)
%3N	Millisecond (3 digits)
%6N	Microsecond (6 digits)
%12N	Picosecond (12 digits)
%15N	Femtosecond (15 digits)
%18N	Attosecond (18 digits)
%21N	Zeptosecond (21 digits)
%24N	Yoctosecond (24 digits)

Time Zone Formatting

Format	Description
%z	Time zone as hour and minute offset from UTC (e.g. +0900)
%:z	Time zone hour and minute offset from UTC with a colon (e.g. +09:00)
%::z	Time zone hour, minute, and second offset from UTC (e.g. +09:00:00)
%:::z	Time zone hour, minute, and second offset from UTC (e.g. +09, +09:30, +09:30:30)
%Z	Time zone abbreviation name or similar information

Weekday Formatting

Format	Description
%A	The full weekday name (e.g. Sunday)
%^A	The full weekday name uppercased (e.g. SUNDAY)
%a	The abbreviated weekday name (e.g. Sun)
%^a	The abbreviated weekday name uppercased (e.g. SUN)
%u	Day of the week starting Monday (1..7)
%w	Day of the week starting Sunday (0..6)

Week Formatting

Format	Description
%G	The week-based year
%g	The last 2 digits of the week-based year (00..99)
%V	Week number of the week-based year (01..53)
%U	Week number of the year. Week starts with Sunday (00..53)
%W	Week number of the year. Week starts with Monday (00..53)

Seconds Formatting

Format	Description
%s	Number of seconds since 1970-01-01 00:00:00 UTC
%Q	Number of milliseconds since 1970-01-01 00:00:00 UTC

Literal Strings

Format	Description
%n	Newline character (\n)
%t	Tab character (\t)
%%	Literal ‘%’ character

Combination

Format	Description
%c	Date and time (%a %b %e %T %Y)
%D	Date (%m/%d/%y)
%F	The ISO 8601 date format (%Y-%m-%d)
%v	VMS date (%e-%b-%Y)
%x	Same as %D
%X	Same as %T
%r	12-hour time (%I:%M:%S %p)
%R	24-hour time (%H:%M)
%T	24-hour time (%H:%M:%S)
%+	date(1) (%a %b %e %H:%M:%S %Z %Y)

---

Back to top ↑