Nitro Pro 13 is an older version (originally released around 2019). The current version is Nitro Pro 14. This guide is for users who already own a valid license key for version 13 or need to reinstall it. Using unlicensed or cracked software is illegal and unsafe. Part 1: Download Nitro Pro 13 Nitro no longer prominently features version 13 on its main site, but they maintain official legacy installers for paying customers.