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☁️ Cloud · credits

Protect PDF (Add Password)

Password-protect a PDF with real AES-256 encryption

🪙 1 credits per file

Used once to encrypt this file, then discarded — we can't recover it, so don't forget it.

Up to 200 MB. Files are deleted from the server within 30 minutes.

Encryption details worth knowing

Real AES encryption with shareable passwords

Set an open password plus optional permission limits and get a standards-compliant encrypted PDF any mainstream reader opens normally.

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AES-256 Protection

The same encryption standard Adobe Acrobat uses, applied with qpdf on our server — the lock travels with the file, not with a viewer setting.

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Password Never Stored

Your password is used once, in memory, to encrypt the file and is never written to disk or logged — there is no password database to leak.

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Locks in Every Reader

Anyone receiving the PDF needs the password in any reader or phone viewer — contracts and statements stay sealed over email or shared links.

How it works

  1. 1

    Drop in the PDF and choose a strong password (entered twice to be safe).

  2. 2

    Our server encrypts it with AES-256 via qpdf.

  3. 3

    Download the protected PDF. Files auto-delete in 30 minutes.

Frequently asked questions

How strong is the protection?

AES-256 is the modern PDF encryption standard — with a strong password it can't be practically brute-forced. A short or common password can still be guessed, so use 12+ mixed characters.

What if I forget the password?

We can't recover it — nothing is stored on our side. Keep it in a password manager. Your original file on your device is untouched, so worst case you encrypt a fresh copy.

Are my file and password safe?

The password lives only in server memory for this one job and is never written anywhere; the upload and the encrypted result are auto-deleted within 30 minutes.

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What Is PDF Encryption?

PDF encryption adds a password to a document so that nobody can open it without the key. When you share contracts, financial statements, or personal records over email or a file-sharing link, an unprotected PDF is readable by anyone who gets the link; a password-protected one stays locked in every PDF reader. This tool applies genuine AES-256 encryption with qpdf on our servers — the same modern standard Adobe Acrobat uses — rather than a flimsy viewer-level restriction. It is a credit-based tool: each run spends a small number of credits from your account balance. The protection travels with the file into any reader, so a password is never just a suggestion.

What this tool can do

  • 🔐 Set a password of your choice, typed twice to avoid typos
  • 🛡️ Real AES-256 encryption that works in every PDF reader, not a viewer-level lock
  • 🔑 The password is used once in memory and never stored on our servers
  • ✅ Any reader, from browsers to mobile apps, will ask for the password
  • 🔁 A failed run refunds your credits automatically

When you'll use it

  • 📎 Send a confidential contract as an encrypted attachment and share the password separately
  • 💳 Protect tax records, bank statements, or personal documents on your devices
  • 🤝 Share financial reports with a client behind a password you control
  • 🗄️ Keep archived documents private even if the storage is ever exposed

Your file is uploaded over an encrypted connection to our server, encrypted by qpdf, and automatically deleted afterward; the password exists only in memory during the job and is never stored or logged. The honest limit: a forgotten password cannot be recovered — there is no backdoor by design — so keep a backup of the unencrypted file and choose a password you will remember. Already-protected files need to be unlocked first. Each run costs credits, refunded automatically on failure.

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