Question 1

How strong is the password protection on this?

Accepted Answer

It uses real RC4 128-bit encryption, which protects against casual, opportunistic access -- someone who shouldn't be able to just open the file. It isn't the strongest encryption available and isn't a substitute for stronger measures on genuinely sensitive data against a determined, technical attacker.

Question 2

How do I know the password actually worked?

Accepted Answer

Open the downloaded PDF in any standard PDF reader and confirm it prompts for a password before showing the content -- that's the simplest way to verify it's actually protected.

Question 3

Why RC4 and not AES?

Accepted Answer

Honestly: the encryption library this uses only implements RC4, not AES -- we'd rather tell you that plainly than market a stronger cipher we don't actually use. RC4 128-bit still adds a real password requirement any standard PDF reader will enforce; it's a genuine step up from no protection at all, just not the strongest option that exists.

Question 4

Can I remove a password from a PDF that already has one?

Accepted Answer

Not with this tool -- it only adds protection to a file that doesn't have it yet. There's currently no "unlock" mode for removing an existing password, even if you know it.

Question 5

What happens if I forget the password I set?

Accepted Answer

There's no recovery option -- the password is genuinely required to open the file, with no backdoor or reset. Write it down somewhere safe before you close this tab; a forgotten password means the file is permanently inaccessible through normal means.

Question 6

Is my password sent anywhere?

Accepted Answer

No -- encryption runs entirely in your browser, including deriving the encryption key from your password. Neither your file nor your password ever reaches a server.

Question 7

Can I protect a PDF that's already password-protected?

Accepted Answer

No -- protecting an already-encrypted PDF will fail. Remove the existing password first (in whatever tool originally set it, since this tool can't remove one), then protect the unlocked version with a new password here.

Question 8

Does the password protect against editing, or just opening the file?

Accepted Answer

Just opening -- this sets a password required to view the document's content at all. It doesn't separately restrict printing, copying, or editing once someone has the password and the file is open.

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