Generates a random password drawn from the defined set of characters.

Signature

wp_generate_password( $length = 12, $special_chars = true, $extra_special_chars = false )
length
 (int) The length of password to generate
Default: 12
special_chars
 (boolean) Whether to include standard special characters. Default true.
Default: true
extra_special_chars
 (boolean) Whether to include other special characters. Used when generating secret keys and salts. Default false.
Default: false

Return

(string) The random password

Source

function wp_generate_password( $length = 12, $special_chars = true, $extra_special_chars = false ) {
	$chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
	if ( $special_chars )
		$chars .= '!@#$%^&*()';
	if ( $extra_special_chars )
		$chars .= '-_ []{}<>~`+=,.;:/?|';

	$password = '';
	for ( $i = 0; $i < $length; $i++ ) {
		$password .= substr($chars, wp_rand(0, strlen($chars) - 1), 1);
	}

	/**
	 * Filter the randomly-generated password.
	 *
	 * @since 3.0.0
	 *
	 * @param string $password The generated password.
	 */
	return apply_filters( 'random_password', $password );
}
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