Wordpress - How to get WordPress Time Zone setting?

if you need the gmt_offset then

<?php echo get_option('gmt_offset'); ?>

this will give you an integer like 2 or -2.

and if you need the timezone string use

<?php echo get_option('timezone_string'); ?>

this will give you a string like America/Indianapolis

The unfortunate situation is that there are indeed two different options:

1. Newer timezone_string, which saves PHP–style time zone.
2. Older gmt_offset, which saves numeric float offset in hours.

But in newer environments timezone_string actually overrides gmt_offset, the value returned by the latter will be based on the former. However the opposite isn't true — gmt_offset might be valid, while timezone_string is empty.

WordPress 5.3 had shipped wp_timezone() function, that abstracts this and returns a valid DateTimeZone object, regardless of underlying WP settings.

Before that I had a take on it implemented in my WpDateTime library (for trivia that was used as a basis for core implementation):

class WpDateTimeZone extends \DateTimeZone {
    /**
     * Determine time zone from WordPress options and return as object.
     *
     * @return static
     */
    public static function getWpTimezone() {
        $timezone_string = get_option( 'timezone_string' );
        if ( ! empty( $timezone_string ) ) {
            return new static( $timezone_string );
        }
        $offset  = get_option( 'gmt_offset' );
        $hours   = (int) $offset;
        $minutes = abs( ( $offset - (int) $offset ) * 60 );
        $offset  = sprintf( '%+03d:%02d', $hours, $minutes );
        return new static( $offset );
    }
}

Check the Option Reference page. The option gmt_offset returns an integer. For example, if the timezone is set to Eastern time (e.g. America/New_York), gmt_offset should be -5.