About this tool
Protect PDF adds AES-256 password encryption to your file in one click. Drop the PDF, type a password, and download the encrypted version — only people who know the password can open it. We use the same password as both the open password and the owner (edit/print) password, so anyone you share the password with has full access. The password is sent to the server over HTTPS, used for this request, and not intentionally logged or retained afterward.
We don't enforce a strength policy, but a 12+ character password with a mix of letters, numbers, and symbols — or one generated by a password manager — is the realistic baseline for anything sensitive. The encrypted file is fully self-contained, so the password matters: there is no recovery flow or support email that can reset it. If you forget it, the contents are gone.
How it works
Drop your PDF
Drag a PDF onto the page or click to browse. Files up to 15 MB and 100 pages are supported. Encrypted PDFs need to be unlocked first — use the Unlock tool if your file is already password-protected.
Type the password you want
Anything from 4 characters up. The strength meter is a nudge, not a rule — for documents you actually care about, use 12 or more characters with a mix of letters, numbers, and symbols, or generate one in a password manager.
Click Protect PDF
The file is encrypted with AES-256 in a single round-trip to our server. The password is sent over HTTPS, used to process the request, and is not intentionally logged or retained.
Download the protected file
The encrypted PDF is returned as a fresh download. Anyone who tries to open it — including you — will be prompted for the password.
When to use it
- Sending a sensitive contract over email when you can't trust the recipient's mailbox.
- Sharing financial statements, tax returns, or invoices with an accountant or client.
- Restricting internal documents — HR files, board memos, salary letters — to the people who need them.
- Adding a layer of protection before syncing a PDF to Dropbox, Google Drive, or iCloud.
- Sending IDs, medical records, or other personal documents that shouldn't sit unencrypted in someone's inbox.
Frequently asked questions
- What encryption do you use?
- AES-256, the same algorithm specified in PDF 2.0 and supported by Acrobat, Preview, Foxit, and every other major PDF reader. The password is the only thing that decrypts the file — without it, the contents are unreadable.
- Can I set different passwords for opening and editing?
- Not currently. We set the same password as both the user (open) password and the owner (edit/print) password. PDFs technically support two distinct passwords, but the simpler one-password model covers the common case of "only people I send this to should see it".
- Can you recover a lost password?
- No. We do not intentionally log or retain the password after the request. The PDF is encrypted with AES-256, so there's no backdoor for us or anyone else. If you forget it, the file is unrecoverable. Save it in a password manager before you close the tab.
- Will the protected PDF open on phones and tablets?
- Yes. AES-256 PDF encryption is supported by every actively maintained reader — iOS Files and Preview, Android's built-in viewers, Adobe Reader on every platform, and all major browsers. The recipient just enters the password when opening the file.
- Does this stop someone from screenshotting the document?
- No. Password protection controls who can open the file — it doesn't control what they do once it's open. Anyone with the password can read, copy, screenshot, or print the contents. If you need view-only sharing without copy or print, that's a different problem (and not really solvable with PDFs alone).