Protect PDF
Add a password so only the people you choose can open your PDF. Strong AES-256 encryption, applied on your device.
How to password-protect a PDF
Open your PDF
Drop the file you want to protect.
Set a password
Type a password and confirm it.
Download
Save the encrypted PDF and share the password separately.
Why people use Protect PDF
“It has my Social Security number.”
Encrypt before attaching, share the password by text.
“Tax returns on a shared drive.”
Keep sensitive files locked even if the folder is shared.
“Only the client should open this.”
Protect contracts and reports you send out.
Encryption that happens before anything moves
Most online tools need your unencrypted file and your password on their server. Here, encryption happens in your browser — the unprotected file never leaves your device.
AES-256
The strongest standard PDF encryption.
Local only
File and password stay in your browser.
Opens everywhere
Works in Adobe Reader, Preview, Chrome and other PDF readers.
No account
Nothing to sign up for, nothing stored.
Frequently asked questions
Is it really free?
Yes. No daily limits, no sign-up and no watermark. Because the work happens on your device, it costs us nothing to run — the site is supported by unobtrusive ads.
Are my files uploaded anywhere?
No. Your files are opened and processed by code running in this browser tab. Nothing is sent to a server — you can confirm it in your browser’s Network panel, or by turning off Wi-Fi after the page loads.
How secure is the encryption?
Files are encrypted with AES-256, the strongest encryption in the PDF standard. Security also depends on choosing a long password.
What if I forget the password?
There is no way to recover it — we never see or store it. Keep the password somewhere safe.
Can I remove the password later?
Yes. Use Unlock PDF and enter the password to save an unprotected copy.