Installation - paypal/PayPal-PHP-SDK GitHub Wiki

There are two ways to install PHP SDK, One using composer as your dependency manager. If you prefer not to use composer, and want to download the php zipped package, you could do that by following the Direct Download instructions.

• Using Composer
  or
• Using Direct Download

Prerequisites

• PHP 5.3 or above
• curl, json & openssl extensions must be enabled

Next Step

• Making your First Call