# Unsubscribe link obfusucate email and campaignid via php
To obfuscate the email and campaign ID in an unsubscribe link using PHP, you should **encode the data into a single, signed token (e.g., using `hash_hmac`)** rather than including the raw values in the URL query parameters. This approach prevents bots from harvesting emails and ensures the data's integrity.
1. Generating the Obfuscated Link
First, you need a secret key stored securely on your server. When generating the email, you'll create a unique token for each recipient by combining the email and campaign ID and signing it with your secret key.
php
```
Unsubscribe';
?>
```
2. Processing the Link in `unsubscribe.php`
When a user clicks the link, the `unsubscribe.php` script will validate the token before processing the request.
php
```
```
This method securely encodes the necessary information while preventing the raw email and campaign ID from being openly visible or easily abused.
Best Practice
Consider adding the `List-Unsubscribe` header to your emails. This allows email clients (like Gmail or Outlook) to provide a native "Unsubscribe" button within their interface, improving deliverability and user experience.
php
```
// When sending the email (using PHPMailer as an example):
$mail->addCustomHeader('List-Unsubscribe', '');
$mail->addCustomHeader('List-Unsubscribe-Post', 'List-Unsubscribe=One-Click'); // For one-click handling
```