date_default_timezone_set()
date_default_timezone_set() — Sets the default timezone used by all date/time functions in a script.
Built-in function of PHP 8.5. The manual lists it as available in PHP 5 >= 5.1.0, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.
Signature
date_default_timezone_set(string $timezoneId): bool
Parameters
| Parameter | Type | What it takes |
|---|---|---|
| $timezoneId | string | 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 value
This function returns false if the timezoneId isn't valid, or true otherwise.
Example
A runnable snippet:
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
All PHP 8.5 built-in functions
Reference card built from the PHP manual page date_default_timezone_set() (PHP documentation, CC BY 3.0). The page is generated from the manual, so the wording of the parameter and return value text follows php.net.