PDF Password Protector

Encrypt PDF with a password

100% free. This tool needs our server to do the work, so what you submit is sent there, processed and then discarded - it is never stored.

picture_as_pdf

Click or drag a PDF here

PDF files only

About this tool

Password-protecting a PDF encrypts its contents so the file is unreadable without the password. This is genuine encryption, not a display setting: the bytes on disk are scrambled, so renaming the file, opening it in a different reader or extracting it from an archive does not bypass it. That makes it the practical way to send a contract, payslip or medical record by email, where the message may sit on several servers and be forwarded further than you intended. Two honest limits are worth stating. First, the protection is only as strong as the password - a short or guessable one can be brute-forced offline by anyone holding the file, and no amount of encryption compensates for that. Second, sending the password in the same email as the document defeats the entire exercise, which is a mistake people make constantly. Use a different channel. This conversion runs on the server and the file is deleted afterwards; neither the document nor the password is retained.

Workflow

Assemble and finish a PDF for sending

Combine, order, number, then lock it. Protecting first would block every later step.

  1. 1MergeCombine the separate files into one.Open
  2. 2Reorder pagesPut everything in reading order.Open
  3. 3Add page numbersMakes a long document referenceable.Open
  4. 4WatermarkMark it as a draft or confidential.Open
  5. 5Password protectDo this last - it locks further editing.You are here

How to use this tool

  1. Upload your PDFThe file is processed on the server and deleted once encryption completes.
  2. Set a strong passwordLength matters more than symbols. Sixteen characters or a multi-word passphrase resists offline cracking; "Report2026" does not.
  3. EncryptThe document contents are encrypted so any reader will demand the password before displaying a single page.
  4. Save the password separatelyStore it in a password manager and send it to the recipient by a different channel than the file itself.

Key features

  • Real encryption of the document contents, not a viewing restriction that a different reader can ignore.
  • Works in every standard PDF reader - Adobe, Preview, browser viewers all prompt for the password.
  • Protects the file wherever it travels, including forwarded emails and shared drives.
  • The original unprotected file stays on your device, so you keep an accessible copy.
  • No account and no watermark added.

Common uses

  • Emailing a contract, payslip or tax document that should not be readable if forwarded.
  • Sending medical or legal records where confidentiality is a professional obligation.
  • Sharing financial statements with an accountant or lender.
  • Distributing an internal report that must not circulate freely.
  • Storing sensitive scans in cloud storage that other people can browse.

Tips for better results

  • Send the password through a different channel than the document - a text message or phone call, never the same email.
  • Use a passphrase of several words rather than a short complex password. It is both stronger and easier to communicate over the phone.
  • Keep an unprotected copy for yourself. If you lose the password, the encrypted file is genuinely unrecoverable.
  • Encrypt last, after any compressing, merging or page edits. Encrypted PDFs cannot be processed by other tools until unlocked.
  • For a password you will need to remember rather than store, the Secure Passphrase Generator produces memorable strong options.

Mistakes to avoid

  • Emailing the password alongside the file, which makes the encryption pointless.
  • Choosing a weak password. The file can be attacked offline for as long as an attacker likes, so a guessable password buys almost nothing.
  • Deleting the original and then forgetting the password, which loses the document permanently.
  • Reusing a password across many protected documents, so one leak exposes all of them.
  • Assuming encryption stops a legitimate recipient from copying, printing or forwarding the contents. Once they can open it, they have it.

Frequently asked questions

Upload your PDF above, set a strong password and encrypt. The protected file downloads immediately, and any reader will require that password before showing the contents.

Yes. No account, no watermark and no limit.

Encryption that requires the password to open the document at all, not just to edit it. Adobe Reader, macOS Preview and browser PDF viewers will all prompt before displaying any page.

The file cannot be recovered. Nothing is stored here, and that is the point of encryption - there is no back door or reset. Keep an unprotected original and store the password in a password manager.

It is used to encrypt the file during processing and is not saved or logged. Both the document and the password are discarded once the job completes.

Strong enough to resist offline attack, because anyone holding the file can attempt passwords indefinitely with no rate limit. Sixteen or more characters, or a passphrase of several unrelated words. Short passwords are the weak point in PDF encryption, not the encryption itself.

Yes - the PDF Unlocker produces an unprotected copy when you supply the correct password.

No. Once someone can open the document they can read, copy, print and forward it. Encryption controls who can open the file, not what they do afterwards.

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