PHP Date and Time

PHP Date and Time Functions

PHP has many built-in date and time functions for handling dates and time.

The core functions for date and time is:

• date() - formats a local date and/or a time
• mktime() - returns the Unix timestamp for a date
• strtotime() - converts an English textual datetime string into a Unix timestamp
• time() - returns the current time as a Unix timestamp
• date_default_timezone_set() - sets the default timezone to be used
• date_default_timezone_get() - gets the default timezone

The PHP Date() Function

The date() function is used to format a local date and/or a time to a more readable date and time.

Syntax

date(format, timestamp)

Using the Date() Function

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)
• j - Represents the day of the month (1 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
• F - Represents the month

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

The example below formats the local date in five different ways:

<?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"). "<br>";
echo date('l, F j, Y');
?>

PHP Tip - Automatic Copyright Year

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

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

Display the Time

The date() function is also used to format a local time to a more readable format.

Here are some characters that are commonly used for times:

• H - 24-hour format of an hour (00 to 23)
• 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 am/pm

The example below outputs the current time in two different formats:

<?php
echo "The time is " . date("H:i:s") . "<br>";
echo "The time is " . date("h:i:s a");
?>

The PHP date_default_timezone_set() Function

Note that the date() function will return the current local date/time of your server!

To get the date and time to be correct according to a specific location, also set the timezone you want to use, with the date_default_timezone_set() function.

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

<?php
date_default_timezone_set("America/New_York");
echo "The current date and time is " . date("Y-m-d H:i:s");
?>

The PHP date_default_timezone_get() Function

To return the default timezone used by all date/time functions in the script, use the date_default_timezone_get() function:

<?php
echo date_default_timezone_get();
?>

The PHP mktime() Function

The optional timestamp parameter in the date() function specifies a timestamp. If omitted, the current date and time will be used (as in the examples above).

The mktime() function returns the Unix timestamp for a date. The Unix timestamp is 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 following example returns the Unix timestamp for a date, and then use it to find the day of that specific date:

<?php
// Set the default timezone to use
date_default_timezone_set("UTC");

$d = mktime(0, 0, 0, 10, 3, 1975);
echo "October 3, 1975 was on a " . date("l", $d);
?>

The PHP time() Function

The time() function returns the current time as a Unix timestamp. The Unix timestamp is the number of seconds between the Unix Epoch (January 1 1970 00:00:00 GMT) and the time specified.

Syntax

time()

<?php
echo "Now: " . time();
?>

Here we format the timestamp to a readable date and time:

<?php
// Get the current Unix timestamp
$ts = time();

// Format timestamp
$curDate = date('Y-m-d H:i:s', $ts); 

echo $curDate;
?>

The PHP strtotime() Function

The strtotime() function converts an English textual datetime string into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 GMT).

Syntax

strtotime(datetime_string, basetimestamp)

The strtotime() function is quite clever about converting a string to a date, so you can put in various values:

<?php
$d = strtotime("10:30pm November 15 2025");
echo "Date is " . date("Y-m-d H:i:s", $d) . "<br>";

$d = strtotime("now");
echo "Date is " . date("Y-m-d H:i:s", $d) . "<br>";

$d = strtotime("+5 days");
echo "Date is " . date("Y-m-d H:i:s", $d) . "<br>";

$d = strtotime("+2 weeks 4 days 2 hours 20 seconds");
echo "Date is " . date("Y-m-d H:i:s", $d) . "<br>";

$d = strtotime("last Sunday");
echo "Date is " . date("Y-m-d H:i:s", $d);
?>

Tip: The strtotime() is not perfect, so remember to check the strings you put in there!

More Date Examples

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

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

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

Complete PHP Date Reference

For a complete reference of all date functions, go to our complete PHP Date Reference.

The reference contains a brief description, and examples of use, for each function!