Password Protect PDF

Protect your PDFs online for privacy, security, and peace of mind—free and fast. Add strong encryption to any PDF directly in your browser. No software downloads, no account required.

AES 128-bit encryption
Files deleted after 1 hour
TLS-secured transfers

Reliable PDF Password Protection

Securely share your sensitive information by encrypting your files and requiring a password for access. This is the most effective way to prevent unauthorized viewing of confidential data.

No Data Retention

Your files are always safe with Smallpdf. We use TLS encryption for all data transfers and permanently delete files after one hour. We never save your document passwords.

Works on Mac, Windows, and Linux

Smallpdf is a web application accessible on any device with a browser, including Mac, Windows, Linux, and mobile devices. Open your browser and add a password to your PDF from anywhere — no software required.

Secure Encryption for Maximum Safety

Some PDF passwords can be cracked easily. With our AES 128-bit encryption, it would take thousands of years to break your password using a standard computer.

Password Strength for Added Security

The more complex your password, the safer your file. We recommend using a non-dictionary word of at least 7 characters with numbers, capital letters, and symbols.

Password Protection in the Cloud

No software installation needed. Protect your PDF with a password by uploading it, choosing a strong password, and downloading the secured file — all in your browser.