How do I password protect a PDF?
To password protect a PDF, upload it to FixDoks's Protect PDF tool, type and confirm a password, choose which permissions to allow, then click Protect PDF. The file is locked with AES-256 encryption so it cannot be opened without the password. Your PDF and password are uploaded over HTTPS and deleted after encryption.
Protect PDF at a glance
| Input | |
|---|---|
| Output | AES-256 encrypted PDF |
| Processing | On our server over HTTPS; files are deleted right after conversion |
| Max file size | 50 MB per file |
| Price | Free, no watermark |
| Download | Free Google sign-in |
| Works on | Chrome, Edge, Safari and Firefox on Windows, Mac, Android and iPhone |
How to use Protect PDF with a Password
- Click Select PDF files and choose the PDF to protect.
- Type a password and confirm it. Untick any permission you want to block, such as printing or copying.
- Click Protect PDF and download the locked file. Anyone opening it will be asked for the password.
Keep private documents private
Salary slips, bank statements, medical reports, legal agreements, ID scans and business proposals often travel by email and WhatsApp, where they can be forwarded or left on shared computers. A password on the PDF means that even if the file reaches the wrong person, they cannot open it. Banks and employers use exactly this approach for statements and payslips.
How strong is the protection?
FixDoks encrypts the PDF with AES-256, the strongest encryption in the PDF standard (PDF 2.0 / Acrobat X and later). Every page, image and piece of text is encrypted, not just hidden. Without the password the content is unreadable. The protected file opens in Adobe Acrobat and Reader, Chrome, Edge, Firefox, macOS Preview, and the PDF viewers on Android and iPhone.
Choosing a good password
- Use at least 10 characters, mixing words, numbers and symbols.
- Avoid your name, phone number or date of birth alone; they are the first things anyone would try.
- Send the password through a different channel than the file, for example the PDF by email and the password by SMS or a call.
- Need ideas? Our Password Generator creates strong ones.
Permissions: printing, copying and editing
Besides the open password, you can restrict what people can do once the file is open. Untick Allow printing to stop printing, Allow copying text to stop copy and paste, or Allow editing to block changes and form filling. These restrictions are respected by Adobe Reader and most mainstream viewers. Keep in mind that permission flags are a courtesy the viewer app enforces: they stop casual copying, but they are not as strong as the open password itself.
Do not lose the password
AES-256 has no back door. If you forget the password, nobody, including FixDoks, can open the file. Keep an unprotected original somewhere safe, or store the password in a password manager.
Removing a password later
If you know the password, Unlock PDF removes it and gives you an ordinary PDF again.
Privacy
Protecting several files at once
You can select several PDFs and protect them all with the same password in one go, for example a set of salary slips or monthly statements you are sending to one person. Each file is encrypted separately, and you can download them individually or as a ZIP. If each recipient needs a different password, protect the files one at a time.
Your PDF and the password are used only to create the encrypted file. Both are deleted from our server immediately afterwards and are never logged.