About Password Protect
Password Protect keeps the complete file workflow inside this browser tab. Your selected file, its name, contents, settings, and generated output are not sent to AntiUpload or a cloud conversion service. Ads and aggregate traffic analytics stay outside the processing boundary and receive no file object or working buffer.
Protect PDF adds password encryption to a PDF document. Anyone who opens the file must enter the password to view the content — a standard technique for protecting contracts, medical records, tax returns, and other sensitive documents during transit.
Encryption runs entirely in your browser. Neither your source PDF nor your password is ever transmitted to our servers.
How it works
- Upload your PDFDrop the PDF you want to protect.
- Set a passwordChoose a password of at least 4 characters. Longer passwords are stronger — aim for 12+ characters with mixed types.
- Click ProtectThe PDF is encrypted and made password-required for opening.
When to use Password Protect
Emailing sensitive documents
When emailing contracts, tax forms, or medical records, password-protect first and share the password via a separate channel (text, call).
Protecting archived documents
Documents stored on a shared drive or in cloud storage are safer when encrypted. Set a strong password and back it up in a password manager.
Sending payroll or client records
Encrypt files that contain identifiers or financial details before transfer, then share the password through a different communication channel.
Frequently asked questions
Are the PDF and password sent to AntiUpload?
No. Encryption runs locally in your browser, and the password is used only on your device to create the protected file. Input files are read from browser memory and the output is created locally for your download. AntiUpload does not send file bytes, names, sizes, page counts, contents, passwords, or generated outputs through analytics or advertising requests.
How strong is the encryption?
This tool uses qpdf to apply AES-256 encryption. The encryption is strong, but the document is only as safe as its password, so use a unique password of at least 12 characters and share it through a separate channel.
What if I forget the password?
There is no recovery option — the password is the only way to open the file. Save it in a password manager immediately after protecting.
Can I remove the password later?
Yes, using our Unlock PDF tool. You need the password to unlock.