.strftime ruby
Date (Year, Month, Day): %Y - Year with century (can be negative, 4 digits at least) -0001, 0000, 1995, 2009, 14292, etc. %C - year / 100 (round down. 20 in 2009) %y - year % 100 (00..99) %m - Month of the year, zero-padded (01..12) %_m blank-padded ( 1..12) %-m no-padded (1..12) %B - The full month name (``January'') %^B uppercased (``JANUARY'') %b - The abbreviated month name (``Jan'') %^b uppercased (``JAN'') %h - Equivalent to %b %d - Day of the month, zero-padded (01..31) %-d no-padded (1..31) %e - Day of the month, blank-padded ( 1..31) %j - Day of the year (001..366) Time (Hour, Minute, Second, Subsecond): %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 - Fractional seconds digits, default is 9 digits (nanosecond) %3N millisecond (3 digits) %15N femtosecond (15 digits) %6N microsecond (6 digits) %18N attosecond (18 digits) %9N nanosecond (9 digits) %21N zeptosecond (21 digits) %12N picosecond (12 digits) %24N yoctosecond (24 digits) Time zone: %z - Time zone as hour and minute offset from UTC (e.g. +0900) %:z - hour and minute offset from UTC with a colon (e.g. +09:00) %::z - hour, minute and second offset from UTC (e.g. +09:00:00) %:::z - hour, minute and second offset from UTC (e.g. +09, +09:30, +09:30:30) %Z - Equivalent to %:z (e.g. +09:00) Weekday: %A - The full weekday name (``Sunday'') %^A uppercased (``SUNDAY'') %a - The abbreviated name (``Sun'') %^a uppercased (``SUN'') %u - Day of the week (Monday is 1, 1..7) %w - Day of the week (Sunday is 0, 0..6) ISO 8601 week-based year and week number: The week 1 of YYYY starts with a Monday and includes YYYY-01-04. The days in the year before the first week are in the last week of the previous year. %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) Week number: The week 1 of YYYY starts with a Sunday or Monday (according to %U or %W). The days in the year before the first week are in week 0. %U - Week number of the year. The week starts with Sunday. (00..53) %W - Week number of the year. The week starts with Monday. (00..53) Seconds since the Unix Epoch: %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 string: %n - Newline character (\n) %t - Tab character (\t) %% - Literal ``%'' character Combination: %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)