Redirects in PHP

PHP sends HTTP headers using the header() function. It must be called before any output, including spaces or line breaks before the <?php tag.

Permanent 301 redirect in PHP

Place at the very top of the file:

Modern syntax (PHP 5.4+, recommended):

<?php
http_response_code(301);
header("Location: https://www.example.net/new-page.php");
exit();
?>

Alternative syntax (compatible with all PHP versions):

<?php
header("HTTP/1.1 301 Moved Permanently");
header("Location: https://www.example.net/new-page.php");
exit();
?>

Temporary 302 redirect in PHP

By default, PHP sends a 302 code when you use header("Location: ..."):

<?php
header("Location: https://www.example.net/directory/page.php");
exit();
?>

To be explicit (recommended):

<?php
http_response_code(302);
header("Location: https://www.example.net/directory/page.php");
exit();
?>

Conditional redirect in PHP

Redirect based on browser language:

<?php
$lang = substr($_SERVER['HTTP_ACCEPT_LANGUAGE'], 0, 2);
if ($lang == 'en') {
    header("Location: https://www.example.net/en/");
    exit();
}
?>

Redirect while preserving GET parameters:

<?php
$params = !empty($_SERVER['QUERY_STRING']) ? '?' . $_SERVER['QUERY_STRING'] : '';
http_response_code(301);
header("Location: https://www.example.net/new-page.php" . $params);
exit();
?>