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PHP Date And Time


The PHP Date() Function

The PHP date() function formats a timestamp to a more readable date and time.

Syntax

date(format,timestamp)

Parameter Description
format Required. Specifies the format of the timestamp
timestamp Optional. Specifies a timestamp. Default is the current date and time

Get a Simple Date

The required format parameter of the date() function specifies how to format the date (or time).

Here are some characters that are commonly used for dates:

  • d - Represents the day of the month (01 to 31)
  • m - Represents a month (01 to 12)
  • Y - Represents a year (in four digits)
  • l (lowercase 'L') - Represents the day of the week

Other characters, like"/", ".", or "-" can also be inserted between the characters to add additional formatting.

The example below formats today's date in three different ways:

See this example:

<?php
echo "Today is " . date("Y/m/d") . "<br>";
echo "Today is " . date("Y.m.d") . "<br>";
echo "Today is " . date("Y-m-d") . "<br>";
echo "Today is " . date("l");
?>

PHP Tip - Automatic Copyright Year

Use the date() function to automatically update the copyright year on your website:

See this example:

&copy; 2010-<?php echo date("Y");?>

Get a Simple Time

Here are some characters that are commonly used for times:

  • h - 12-hour format of an hour with leading zeros (01 to 12)
  • i - Minutes with leading zeros (00 to 59)
  • s - Seconds with leading zeros (00 to 59)
  • a - Lowercase Ante meridiem and Post meridiem (am or pm)

The example below outputs the current time in the specified format:

See this example:

<?php
echo "The time is " . date("h:i:sa");
?>

Get Your Time Zone

If the time you got back from the code is not the right time, it's probably because your server is in another country or set up for a different timezone.

So, if you need the time to be correct according to a specific location, you can set a timezone to use.

The example below sets the timezone to "America/New_York", then outputs the current time in the specified format:

See this example:

<?php
date_default_timezone_set("America/New_York");
echo "The time is " . date("h:i:sa");
?>

Create a Date With PHP mktime()

The optional timestamp parameter in the date() function specifies a timestamp. If you do not specify a timestamp, the current date and time will be used (as shown in the examples above).

The mktime() function returns the Unix timestamp for a date. The Unix timestamp contains the number of seconds between the Unix Epoch (January 1 1970 00:00:00 GMT) and the time specified.

Syntax

mktime(hour,minute,second,month,day,year)

The example below creates a date and time from a number of parameters in the mktime() function:

See this example:

<?php
$d=mktime(11, 14, 54, 8, 12, 2014);
echo "Created date is " . date("Y-m-d h:i:sa", $d);
?>

Create a Date From a String With PHP strtotime()

The PHP strtotime() function is used to convert a human readable string to a Unix time.

Syntax

strtotime(time,now)

The example below creates a date and time from the strtotime() function:

See this example:

<?php
$d=strtotime("10:30pm April 15 2014");
echo "Created date is " . date("Y-m-d h:i:sa", $d);
?>

PHP is quite clever about converting a string to a date, so you can put in various values:

See this example:

<?php
$d=strtotime("tomorrow");
echo date("Y-m-d h:i:sa", $d) . "<br>";

$d=strtotime("next Saturday");
echo date("Y-m-d h:i:sa", $d) . "<br>";

$d=strtotime("+3 Months");
echo date("Y-m-d h:i:sa", $d) . "<br>";
?>

However, strtotime() is not perfect, so remember to check the strings you put in there.


More Date Examples

The example below outputs the dates for the next six Saturdays:

See this example:

<?php
$startdate = strtotime("Saturday");
$enddate = strtotime("+6 weeks", $startdate);

while ($startdate < $enddate) {
  echo date("M d", $startdate) . "<br>";
  $startdate = strtotime("+1 week", $startdate);
}
?>

The example below outputs the number of days until 4th of July:

See this example:

<?php
$d1=strtotime("July 04");
$d2=ceil(($d1-time())/60/60/24);
echo "There are " . $d2 ." days until 4th of July.";
?>