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Your files stay on your device

File processing runs in your browser. Documents are not uploaded to our servers. The site may download processing engines and send usage or feedback events without file contents.

How we handle your data

Protect PDF

Set an AES-256 opening password of at least 12 characters on a technical PDF record before it is stored or transmitted. Files stay in your browser.

Small converter download on first use.

One PDF, up to 20 MiB. The original file stays unchanged.

Use at least 12 characters. Keep a copy: there is no password recovery.

Try an example

Download sample

The downloaded PDF should require your chosen password and retain both pages.

What to expect

Protection uses AES-256 and sets a password to open the PDF; after opening, printing, copying and editing are not restricted. Unlocking requires the existing password; this tool does not guess passwords. Changing a PDF can invalidate digital signatures.

Processing stops after 30 seconds. Protected input can be up to 30 MiB; output is limited to 30 MiB.

The first run may download converter files and take a moment. If it fails, check your connection or try a smaller file. Cancel stops active processing; you can choose another file and retry.

Engine licenses and source code

A practical guide

Restrict access to the stored record.

  1. Choose the record PDF and set a password of 12 or more characters.
  2. Run Protect PDF to produce the encrypted file.
  3. Verify the file opens only with the correct password before archiving it.

Try this example

Protect a calibration record with the password datum-record-778812; the file should reject an incorrect password and open with the correct one.

Before you start: Encryption restricts opening only; printing, copying and editing are not restricted for anyone who supplies the correct password.