Runtime Configuration

The behaviour of these functions is affected by settings in php.ini.

Date/Time Configuration Options
Name Default Changeable Changelog
date.default_latitude "31.7667" INI_ALL  
date.default_longitude "35.2333" INI_ALL  
date.sunrise_zenith "90.833333" INI_ALL Prior to PHP 8.0.0, the default was "90.583333"
date.sunset_zenith "90.833333" INI_ALL Prior to PHP 8.0.0, the default was "90.583333"
date.timezone "UTC" INI_ALL From PHP 8.2, a warning is emitted when setting this to an invalid value or an empty string.
For further details and definitions of the INI_* modes, see the Where a configuration setting may be set.

Here's a short explanation of the configuration directives.

date.default_latitude float

The default latitude ranging from 0 at the equator, to +90 northward, and -90 southward.

date.default_longitude float

The default longitude ranging from 0 at the prime meridian to +180 eastward and −180 westward.

date.sunrise_zenith float

The default sunrise zenith.

The default value is 90°50'. The additional 50' is due to two components: the Sun's radius, which is 16', and the atmospheric refraction, which is 34'.

date.sunset_zenith float

The default sunset zenith.

date.timezone string

The default timezone used by all date/time functions. The precedence order for which timezone is used if none is explicitly mentioned is described in the date_default_timezone_get page. See List of Supported Timezones for a list of supported timezones.

Note: The first four configuration options are currently only used by date_sunrise and date_sunset.