PHP Manual: Format a Unix timestamp

Description

string date(string $format, intnull $timestamp = null)

Returns a string formatted according to the given format string using the given integer timestamp (Unix timestamp) or the current time if no timestamp is given. In other words, timestamp is optional and defaults to the value of time.

Warning

Unix timestamps do not handle timezones. Use the DateTimeImmutable class, and its DateTimeInterface::format formatting method to format date/time information with a timezone attached.

Parameters

format: Format accepted by DateTimeInterface::format.

Note: date will always generate 000000 as microseconds since it takes an int parameter, whereas DateTimeInterface::format does support microseconds if an object of type DateTimeInterface was created with microseconds.
timestamp: The optional timestamp parameter is an int Unix timestamp that defaults to the current local time if timestamp is omitted or null. In other words, it defaults to the value of time.

Return Values

Returns a formatted date string.

Errors/Exceptions

Every call to a date/time function will generate a E_WARNING if the time zone is not valid. See also date_default_timezone_set

Changelog

Version	Description
8.0.0	`timestamp` is nullable now.

Examples

Example #1 date examples

<?php
// set the default timezone to use.
date_default_timezone_set('UTC');


// Prints something like: Monday
echo date("l");

// Prints something like: Monday 8th of August 2005 03:12:46 PM
echo date('l jS \of F Y h:i:s A');

// Prints: July 1, 2000 is on a Saturday
echo "July 1, 2000 is on a " . date("l", mktime(0, 0, 0, 7, 1, 2000));

/* use the constants in the format parameter */
// prints something like: Wed, 25 Sep 2013 15:28:57 -0700
echo date(DATE_RFC2822);

// prints something like: 2000-07-01T00:00:00+00:00
echo date(DATE_ATOM, mktime(0, 0, 0, 7, 1, 2000));
?>

You can prevent a recognized character in the format string from being expanded by escaping it with a preceding backslash. If the character with a backslash is already a special sequence, you may need to also escape the backslash.

Example #2 Escaping characters in date

<?php
// prints something like: Wednesday the 15th
echo date('l \t\h\e jS');
?>

It is possible to use date and mktime together to find dates in the future or the past.

Example #3 date and mktime example

<?php
$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);
?>

Note:
This can be more reliable than simply adding or subtracting the number of seconds in a day or month to a timestamp because of daylight saving time.

Some examples of date formatting. Note that you should escape any other characters, as any which currently have a special meaning will produce undesirable results, and other characters may be assigned meaning in future PHP versions. When escaping, be sure to use single quotes to prevent characters like \n from becoming newlines.

Example #4 date Formatting

<?php
// Assuming today is March 10th, 2001, 5:16:18 pm, and that we are in the
// Mountain Standard Time (MST) Time Zone

$today = date("F j, Y, g:i a");                 // March 10, 2001, 5:16 pm
$today = date("m.d.y");                         // 03.10.01
$today = date("j, n, Y");                       // 10, 3, 2001
$today = date("Ymd");                           // 20010310
$today = date('h-i-s, j-m-y, it is w Day');     // 05-16-18, 10-03-01, 1631 1618 6 Satpm01
$today = date('\i\t \i\s \t\h\e jS \d\a\y.');   // it is the 10th day.
$today = date("D M j G:i:s T Y");               // Sat Mar 10 17:16:18 MST 2001
$today = date('H:m:s \m \i\s\ \m\o\n\t\h');     // 17:03:18 m is month
$today = date("H:i:s");                         // 17:16:18
$today = date("Y-m-d H:i:s");                   // 2001-03-10 17:16:18 (the MySQL DATETIME format)
?>

To format dates in other languages, IntlDateFormatter::format can be used instead of date.

Notes

Note:
To generate a timestamp from a string representation of the date, you may be able to use strtotime. Additionally, some databases have functions to convert their date formats into timestamps (such as MySQL's » UNIX_TIMESTAMP function).

Tip

Timestamp of the start of the request is available in $_SERVER['REQUEST_TIME'].