Here is a table for formatting the PHP function date() and the letters used to represent different parts of a timestamp.
| a | ‘am’ or ‘pm’ |
| A | ‘AM’ or ‘PM’ |
| B | Swatch Internet time |
| d | day of the month, 2 digits with leading zeros; i.e. ’01’ to ’31’ |
| D | day of the week, textual, 3 letters; i.e. ‘Fri’ |
| F | month, textual, long; i.e. ‘January’ |
| g | hour, 12-hour format without leading zeros; i.e. ‘1’ to ’12’ |
| G | hour, 24-hour format without leading zeros; i.e. ‘0’ to ’23’ |
| h | hour, 12-hour format; i.e. ’01’ to ’12’ |
| H | hour, 24-hour format; i.e. ’00’ to ’23’ |
| i | minutes; i.e. ’00’ to ’59’ |
| I (capital i) | ‘1’ if Daylight Savings Time, ‘0’ otherwise. |
| j | day of the month without leading zeros; i.e. ‘1’ to ’31’ |
| l (lowercase ‘L’) | day of the week, textual, long; i.e. ‘Friday’ |
| L | boolean for whether it is a leap year; i.e. ‘0’ or ‘1’ |
| m | month; i.e. ’01’ to ’12’ |
| M | month, textual, 3 letters; i.e. ‘Jan’ |
| n | month without leading zeros; i.e. ‘1’ to ’12’ |
| r | RFC 822 formatted date; i.e. ‘Thu, 21 Dec 2000 16:01:07 +0200’ (added in PHP 4.0.4) |
| s | seconds; i.e. ’00’ to ’59’ |
| S | English ordinal suffix, textual, 2 characters; i.e. ‘th’, ‘nd’ |
| t | number of days in the given month; i.e. ’28’ to ’31’ |
| T | Timezone setting of this machine; i.e. ‘MDT’ |
| U | seconds since the epoch |
| w | day of the week, numeric, i.e. ‘0’ (Sunday) to ‘6’ (Saturday) |
| Y | year, 4 digits; i.e. ‘1999’ |
| y | year, 2 digits; i.e. ’99’ |
| z | day of the year; i.e. ‘0’ to ‘365’ |
| Z | timezone offset in seconds (i.e. ‘-43200’ to ‘43200’). The offset for timezones west of UTC is always negative, and for those east of UTC is always positive. |