PDF security
Understand what PDF passwords can and cannot protect
An open password encrypts a PDF so a reader needs the secret to decrypt it. Editing, printing, or copying restrictions are viewer-enforced permissions and may not stop a recipient who can already open the document.
Workflow
Choose the actual control
Use an open password when the file must remain unreadable without a secret; use a controlled sharing system when access must be revoked, audited, or expired.
Create and transmit the password safely
Use a long unique passphrase, protect a final verified copy, and send the password through a different trusted channel from the document.
Test recovery before distribution
Close the session, reopen the saved PDF with the intended readers, verify the password, and retain an authorized unencrypted source or recovery process.
Limits to understand
Password protection cannot revoke a file already decrypted or copied, stop screenshots, repair forgotten secrets, or guarantee that every viewer honors print and edit permissions. Rewriting may affect forms and signatures.
Privacy mode
Supported protection and unlocking run locally; passwords are used in memory and must not enter URLs, analytics, or storage. Device security, clipboard managers, extensions, and password-sharing channels remain separate risks.
Verify the result
Open the result without cached credentials, confirm a wrong password fails and the right one succeeds, inspect important document structures, and test at least one reader used by the recipient.
Frequently asked questions
Can the unlock tool recover a forgotten password?
No. It requires a valid password and does not crack, bypass, or recover encryption credentials.
Does disabling printing prevent screenshots?
No. Viewer permissions are not a reliable barrier once content is visible. Use disclosure minimization and an appropriate controlled delivery system.