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Drag and drop your PDF file or click to select it from your device. Your file stays in your browser — nothing is uploaded to any server.
Enter the password you want to use to protect the PDF. Anyone who wants to open the file will need this password.
Click "Protect PDF" and download the encrypted file. The original file remains unchanged.
Your files never leave your device. All encryption happens in your browser using WebAssembly — no server uploads, no third-party access.
No registration, no file limits, no watermarks. Protect as many PDFs as you need, completely free.
Protected PDFs work with all major readers including standard PDF readers, Chrome, Firefox, Edge, and Preview on Mac.
Protect confidential business documents before sharing via email
Secure personal tax returns and financial statements
Lock legal contracts so only authorized parties can open them
Add a password to medical records or insurance documents
| Format | Description | Best For |
|---|---|---|
| PDF 1.4+ | Standard PDF with password encryption | Universal compatibility with all readers |
| PDF/A | Archival PDFs can be protected | Long-term secure document storage |
Use a strong password with at least 8 characters, mixing letters, numbers, and symbols
Store the password separately from the PDF — if you lose it, the file cannot be recovered
Always keep an unprotected backup copy in a secure location
Test opening the protected PDF in different readers to confirm compatibility
FyleTools encrypts your PDF entirely in your browser using WebAssembly and the lopdf library compiled from Rust. Your document and password are never sent to any server — the encryption algorithm runs locally on your device. This means confidential contracts, financial records, and personal files stay completely private throughout the process.