Date/time checkdate Validate a date/time int checkdate int month int day int year Returns true if the date given is valid; otherwise returns false. Checks the validity of the date formed by the arguments. A date is considered valid if: year is between 0 and 32767 inclusive month is between 1 and 12 inclusive day is within the allowed number of days for the given month. Leap years are taken into consideration. date Format a local time/date string date string format int timestamp Returns a string formatted according to the given format string using the given timestamp or the current local time if no timestamp is given. The following characters are recognized in the format string: a - "am" or "pm" A - "AM" or "PM" 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" h - hour, 12-hour format; i.e. "01" to "12" H - hour, 24-hour format; i.e. "00" to "23" 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" i - minutes; i.e. "00" to "59" 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" n - month without leading zeros; i.e. "1" to "12" M - month, textual, 3 letters; i.e. "Jan" 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" 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") Unrecognized characters in the format string will be printed as-is. The "Z" format will always return "0" when using gmdate. print (date ("l dS of F Y h:i:s A")); print ("July 1, 2000 is on a " . date ("l", mktime(0,0,0,7,1,2000))); It is possible to use date and mktime together to find dates in the future or the past. $tomorrow = mktime (0,0,0,date("m") ,date("d")+1,date("Y")); $lastmonth = mktime (0,0,0,date("m")-1,date("d"), date("Y")); $nextyear = mktime (0,0,0,date("m"), date("d"), date("Y")+1); To format dates in other languages, you should use the setlocale and strftime functions. See also gmdate and mktime. getdate Get date/time information array getdate int timestamp Returns an associative array containing the date information of the timestamp as the following array elements: "seconds" - seconds "minutes" - minutes "hours" - hours "mday" - day of the month "wday" - day of the week, numeric "mon" - month, numeric "year" - year, numeric "yday" - day of the year, numeric; i.e. "299" "weekday" - day of the week, textual, full; i.e. "Friday" "month" - month, textual, full; i.e. "January" gettimeofday Get current time array gettimeofday void This is an interface to gettimeofday(2). It returns an associative array containing the data returned from the system call. "sec" - seconds "usec" - microseconds "minuteswest" - minutes west of Greenwich "dsttime" - type of dst correction gmdate Gormat a GMT/CUT date/time string gmdate string format int timestamp Identical to the date function except that the time returned is Greenwich Mean Time (GMT). For example, when run in Finland (GMT +0200), the first line below prints "Jan 01 1998 00:00:00", while the second prints "Dec 31 1997 22:00:00". echo date ("M d Y H:i:s", mktime (0,0,0,1,1,1998)); echo gmdate ("M d Y H:i:s", mktime (0,0,0,1,1,1998)); See also date, mktime, and gmmktime. gmmktime Get UNIX timestamp for a GMT date int gmmktime int hour int minute int second int month int day int year int is_dst Identical to mktime except the passed parameters represents a GMT date. gmstrftime Format a GMT/CUT time/date according to locale settings string gmstrftime string format int timestamp Behaves the same as strftime except that the time returned is Greenwich Mean Time (GMT). For example, when run in Eastern Standard Time (GMT -0500), the first line below prints "Dec 31 1998 20:00:00", while the second prints "Jan 01 1999 01:00:00". setlocale ('LC_TIME', 'en_US'); echo strftime ("%b %d %Y %H:%M:%S", mktime (20,0,0,12,31,98))."\n"; echo gmstrftime ("%b %d %Y %H:%M:%S", mktime (20,0,0,12,31,98))."\n"; See also strftime. microtime Return current UNIX timestamp with microseconds string microtime Returns the string "msec sec" where sec is the current time measured in the number of seconds since the Unix Epoch (0:00:00 January 1, 1970 GMT), and msec is the microseconds part. This function is only available on operating systems that support the gettimeofday() system call. See also time. mktime Get UNIX timestamp for a date int mktime int hour int minute int second int month int day int year int is_dst Warning: Note the strange order of arguments, which differs from the order of arguments in a regular UNIX mktime() call and which does not lend itself well to leaving out parameters from right to left (see below). It is a common error to mix these values up in a script. Returns the Unix timestamp corresponding to the arguments given. This timestamp is a long integer containing the number of seconds between the Unix Epoch (January 1 1970) and the time specified. Arguments may be left out in order from right to left; any arguments thus omitted will be set to the current value according to the local date and time. is_dst can be set to 1 if the time is during daylight savings time, 0 if it is not, or -1 (the default) if it is unknown whether the time is within daylight savings time or not. is_dst was added in 3.0.10. Mktime is useful for doing date arithmetic and validation, as it will automatically calculate the correct value for out-of-range input. For example, each of the following lines produces the string "Jan-01-1998". echo date ("M-d-Y", mktime (0,0,0,12,32,1997)); echo date ("M-d-Y", mktime (0,0,0,13,1,1997)); echo date ("M-d-Y", mktime (0,0,0,1,1,1998)); echo date ("M-d-Y", mktime (0,0,0,1,1,98)); year may be a two or four digit value, with values between 0-69 mapping to 2000-2069 and 70-99 to 1970-1999 (on systems where time_t is a 32bit signed integer, as most common today, the valid range for year is somewhere between 1902 and 2037). The last day of any given month can be expressed as the "0" day of the next month, not the -1 day. Both of the following examples will produce the string "The last day in Feb 2000 is: 29". $lastday = mktime (0,0,0,3,0,2000); echo strftime ("Last day in Feb 2000 is: %d", $lastday); $lastday = mktime (0,0,0,4,-31,2000); echo strftime ("Last day in Feb 2000 is: %d", $lastday); See also date and time. strftime format a local time/date according to locale settings string strftime string format int timestamp Returns a string formatted according to the given format string using the given timestamp or the current local time if no timestamp is given. Month and weekday names and other language dependent strings respect the current locale set with setlocale. The following conversion specifiers are recognized in the format string: %a - abbreviated weekday name according to the current locale %A - full weekday name according to the current locale %b - abbreviated month name according to the current locale %B - full month name according to the current locale %c - preferred date and time representation for the current locale %d - day of the month as a decimal number (range 00 to 31) %H - hour as a decimal number using a 24-hour clock (range 00 to 23) %I - hour as a decimal number using a 12-hour clock (range 01 to 12) %j - day of the year as a decimal number (range 001 to 366) %m - month as a decimal number (range 1 to 12) %M - minute as a decimal number %p - either `am' or `pm' according to the given time value, or the corresponding strings for the current locale %S - second as a decimal number %U - week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week %W - week number of the current year as a decimal number, starting with the first Monday as the first day of the first week %w - day of the week as a decimal, Sunday being 0 %x - preferred date representation for the current locale without the time %X - preferred time representation for the current locale without the date %y - year as a decimal number without a century (range 00 to 99) %Y - year as a decimal number including the century %Z - time zone or name or abbreviation %% - a literal `%' character setlocale ("LC_TIME", "C"); print (strftime ("%A in Finnish is ")); setlocale ("LC_TIME", "fi_FI"); print (strftime ("%A, in French ")); setlocale ("LC_TIME", "fr_CA"); print (strftime ("%A and in German ")); setlocale ("LC_TIME", "de_DE"); print (strftime ("%A.\n")); This example works if you have the respective locales installed in your system. See also setlocale and mktime. time Return current UNIX timestamp int time Returns the current time measured in the number of seconds since the Unix Epoch (January 1 1970 00:00:00 GMT). See also date.