Keep your password safe - it cannot be recovered. Anyone without the password will be asked for it when opening the PDF.
Download Protected PDFAbout Password Protect PDF
This free online tool adds a password to your PDF so anyone opening the file must enter the password first. Whether you are sending contracts, mark sheets, invoices or personal documents, your file stays locked until the right person unlocks it.
The protection is applied inside the PDF structure itself using the industry-standard encryption that Adobe Reader, Chrome, Edge, mobile viewers and every major PDF app understands. Text, images and layout remain exactly as they were - only access changes.
How Password Protection Works
Your PDF is re-saved with standard PDF encryption (RC4 128-bit security handler). Every internal stream and string is encrypted with keys derived from your password. When someone tries to open the protected file, the PDF reader automatically shows a password prompt before displaying anything.
Features of Password Protect PDF
- Set a password that is asked every time the PDF is opened
- Optional permission controls - allow printing and/or text copying after unlock
- Content stays untouched - no quality loss, no page conversion
- Show/hide password toggle while typing
- Detects already-protected PDFs and warns you
- Free, no signup, no watermark, 100% private - files never leave your device
How to Add a Password to a PDF
- Select your PDF or drag & drop it into the upload area.
- Type your password and confirm it.
- Optionally tick Allow printing or Allow copying text.
- Click Protect PDF, then Download Protected PDF.
Password Protect PDF FAQ
Will the PDF ask for a password when opened?
Yes. As soon as anyone opens the downloaded file in Adobe Reader, Chrome, a phone or any PDF viewer, a password prompt appears. Without the correct password the content stays hidden.
Is my file uploaded to a server?
No. Encryption runs completely inside your browser. Your PDF never leaves your device.
Can I recover the password if I forget it?
No. There is no backdoor. Save your password somewhere safe before protecting important documents.
What do the printing and copying options do?
After the correct password is entered, these options decide whether the unlocked document may be printed and whether its text may be selected and copied. By default both are restricted.
Which PDF viewers support the protection?
All modern viewers - Adobe Acrobat Reader, browsers (Chrome, Firefox, Edge, Safari), mobile apps and preview tools - understand this standard encryption.
Is it free?
Yes - completely free with no signup and no limits.