Add password protection to your PDF documents securely in your browser.
Password-protecting a PDF is the easiest way to secure sensitive documents before sharing them. With PDF Toolkit's free Protect PDF tool, you can apply strong 128-bit AES encryption to any document directly in your browser. Whether you are sending financial reports, legal agreements, medical records, or personal documents, adding a password ensures only authorized recipients can view the contents. Since all encryption happens locally on your device using WebAssembly, your files are never uploaded to our servers, giving you complete privacy and peace of mind. Simply upload your PDF, choose a secure password, and download the encrypted file immediately.
Click "Drop PDF here" or click the upload area to select your document.
Enter a strong password in both the Password and Confirm Password fields.
Click "Protect & Download". The encryption process is instant and entirely local.
Your password-protected PDF will download automatically. You can also save it to your account history.
Want to learn more? Read our PDF guides and tutorials →