Protect PDF
Password-encrypt a PDF and optionally limit printing, copying, and edits
Protect PDF — lock opening and limit what readers can do
Protect PDF encrypts a document with a password so strangers cannot open it casually, and optionally sets owner-side restrictions on printing, modifying, copying, or annotating. Encryption runs in your browser with pdf-lib — free on pdfLaunch.
Already locked and need access again? Use Unlock PDF. Only a visible DRAFT stamp? That is Add Watermark. Hiding secrets permanently? Use Redact PDF.
Passwords and restrictions you can set
User password (to open)
Anyone opening the file must enter this password. Leave it blank only when you want an owner-password / restrictions pack without an open gate.
Owner password (for permissions)
Controls who can change the restriction flags later. If you leave owner blank, the tool reuses your user password as owner.
Four restriction toggles
Optionally restrict printing, modifying, copying, and annotating. Unchecked means that action stays allowed under the PDF permission flags.
Honest limits
This is standard PDF password encryption — not enterprise DRM. Determined attackers with the file may still try to crack weak passwords; use a strong phrase.
How to password-protect a PDF here
Upload the PDF
Choose a file up to 25 MB from your device or cloud picker.
Set passwords and limits
Enter a user and/or owner password, tick any restrictions you need, then click Apply Protection.
Download the locked PDF
Save pdflaunch-protected-….pdf and confirm the open password works in your reader.
When people lock a PDF
A password is not the same as removing content. For irreversible black-out use Redact PDF. For a visible status stamp use Add Watermark.
Protect vs unlock, watermark, redact, and sign
Encryption happens in your browser
pdf-lib applies passwords locally — we do not receive your open password or the unprotected file for convert
- Local encrypt: the protected PDF is built in the browser and downloaded from an object URL.
- No protect upload: unlike OCR or Office converters, Protect does not send the PDF for server encryption.
- Optional cloud pickers: Drive / Dropbox / OneDrive only fetch the file into the browser session.
- No account wall: protect and download without registering.
Protect PDF FAQ
What is the difference between user and owner password?
The user password is required to open the PDF. The owner password governs permission changes (print/copy/modify/annotate flags).
Can I set restrictions without an open password?
Yes — leave the user field empty and set an owner password, then tick the restrictions you need. Readers can open freely but permission flags still apply in supporting readers.
Which actions can I restrict?
Printing, modifying, copying, and annotating. Each checkbox turns that permission off when selected.
Is Protect the same as a watermark?
No. A watermark is a visible stamp. Protect encrypts the file and/or sets permission flags.
Does this permanently delete sensitive text?
No. Passwords gate access; they do not erase content. Use Redact PDF for irreversible removal.
How large can the PDF be for protection?
Up to 25 MB.
Are my files uploaded when I protect a PDF?
No. Encryption runs in your browser with pdf-lib.
What if I forget the password later?
pdfLaunch cannot recover it. Store the password safely. Unlock PDF only works when you still know the open password.
Do all PDF readers honor print/copy restrictions?
Most mainstream readers respect the flags, but they are not unbreakable DRM. Treat them as soft limits plus a strong open password when secrecy matters.
Do I need a pdfLaunch account to protect a PDF?
No. Upload, set passwords, and download without registering.