Protect PDF
Password-Protect a PDF Online
Lock a document so only people with the password can open it. FileNova encrypts your PDF with AES-256 — the strongest scheme the PDF specification defines — entirely in memory, then hands the protected file straight back to you.
🔐 AES-256 encryption🧠 In-memory processing🖨️ Reader permissions🚫 Password never stored
Drop a PDF file to protect, or browse
Upload exactly 1 PDF document (up to 25 MB). It is encrypted in memory and never stored.
Browse filesfrom device
How FileNova Protects PDFs
1
Upload your PDF
Drag and drop a PDF up to 25 MB. FileNova checks the file signature and page count before anything else happens.
2
Choose a password
Enter the password twice so a typo can never lock you out, and decide whether readers may print, copy, edit, or comment.
3
Download the protected file
Every page, image, and string in the document is encrypted. Opening the file in any reader now asks for your password.
Frequently asked
- Can FileNova recover a lost password?
- No. The password is used to derive the encryption key and is then discarded — it is never stored or logged, so a lost password means a document that cannot be reopened.
- Which encryption is used?
- AES-256 with revision 6 of the PDF standard security handler, readable by Acrobat 9 and newer, macOS Preview, Chrome, Firefox, and Edge.
- Is my document stored on a server?
- No. The upload is processed in memory and released as soon as the protected file is returned. Nothing is written to disk.
- Can I protect an already-encrypted PDF?
- Not directly — remove the existing password first. FileNova detects already-protected files and tells you instead of producing a broken document.