Every design decision begins with the safety and privacy of your data in mind. We can't read your files, and no one else can either. Privacy isn’t an optional mode — it’s just the way our services work.
When you register an account, your password never leaves your device. A secure key is generated using PBKDF2 based on your password, and the key is ued for authentication purpose.
When you upload a file to your account, edit a PDF file, or compress a PDF file, all files are encrypted using 256-bit AES and then stored on our servers. The file encryption keys are generated using PBKDF2 based on your password (or a secure random password if you do not log in), and each file has a unique encryption key. Unlike other providers, we do not have access to your files.
With end-to-end encryption, data is encrypted and decrypted only at the "end points". That means that service providers in the middle don't have access to the keys, and therefore can't read your data.
If your data is "encrypted" but someone else has the key to unlock it, then it's not truly safe. A rogue employee or a hacker could view your data without your permssion. End-to-end encryption prevents your data from falling into the wrong hands because nobody but yourself has the key to unlock your data.
When you use our file sending service, your files are encrypted using 256-bit AES in browser and then transfer through secure TLS 1.2 to our servers. The file encryption keys are generated using PBKDF2 based on your password, and each file has a unique encryption key. The keys never leave your device and you're the only one who has them – unless you decide to share them.