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date_default_timezone_set

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

date_default_timezone_set — Sets the default timezone used by all date/time functions in a script

Description

date_default_timezone_set(string $timezoneId): bool

date_default_timezone_set() sets the default timezone used by all date/time functions.

Instead of using this function to set the default timezone in your script, you can also use the INI setting date.timezone to set the default timezone.

Parameters

timezoneId

The timezone identifier, like UTC, Africa/Lagos, Asia/Hong_Kong, or Europe/Lisbon. The list of valid identifiers is available in the List of Supported Timezones.

Return Values

This function returns false if the timezoneId isn't valid, or true otherwise.

Examples

Example #1 Getting the default timezone

<?php
date_default_timezone_set('America/Los_Angeles');

$script_tz = date_default_timezone_get();
$ini_tz = ini_get('date.timezone');

if (strcmp($script_tz, $ini_tz)){
    echo 'Script timezone differs from ini-set timezone.';
} else {
    echo 'Script timezone and ini-set timezone match.';
}

See Also

© 1997–2025 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.date-default-timezone-set.php