Lock PDF
About this Tool
Add an open password to any PDF so only recipients with the password can view it. Ideal for securely sharing confidential documents and preventing unauthorized access. All encryption runs entirely in your browser — no files are uploaded to a server.
Processed safely on your device
Everything happens in your browser on this device. Your files are never sent to our servers—so you can use it with peace of mind.
How to Use
Upload the PDF file you want to protect into the dropzone.
Enter a strong open password and re-enter it in the confirmation field.
Click 'Lock PDF' to download the encrypted file instantly.
Key Scenarios & Use Cases
Protecting Confidential Contracts and NDAs
Password-lock a non-disclosure agreement before emailing it so that only designated recipient executives can access the contents.
Restricting Access to Internal Payroll and HR Files
Encrypt individual compensation sheets and performance appraisals to safeguard personal employee data during distribution.
Securing Financial Forecasts and Investor Pitch Decks
Apply access restrictions to unreleased earnings models and confidential pitch materials to prevent unauthorized corporate leaks.
Frequently Asked Questions (FAQ)
RC4 128-bit encryption via the pdf-lib-with-encrypt library. The resulting file is fully compatible with Adobe Acrobat, browser PDF viewers, and mobile readers.
The file cannot be recovered without the password. Make sure to store it in a secure password manager before locking the document.
No. All encryption runs 100% locally in your client device's browser memory. Your credentials and documents never touch external servers.