Why password-protect a PDF?
Not every document should be freely readable by anyone who gets the file. Password protection is the first line of defence for:
Legal contracts
Ensure only named parties can open agreements before signing
Financial reports
Restrict access to salary data, budgets, and financial statements
Medical records
Protect sensitive health information shared electronically
Personal ID copies
Add a layer of security to passport or ID scans sent by email
How to add a password to a PDF
Open Protect PDF
Go to yumpdf.com/protect-pdf. No account required.
Upload your PDF
Drag your file onto the drop zone. Your document is processed locally — it never leaves your browser.
Set a password
Enter the password you want to use. You'll need to confirm it to prevent typos. Keep a secure record of it — there's no recovery option.
Download the protected PDF
Click "Protect PDF". The encrypted file downloads immediately, ready to share.
What encryption does YumPDF use?
YumPDF applies AES-256 encryption — the same standard used by banks and governments. A correctly chosen password with AES-256 encryption is practically unbreakable with current technology. The PDF standard allows two types of password:
User password (open password)
Required to open and view the document. Anyone without this password sees a password prompt instead of the content.
Owner password (permissions password)
Controls what an authorised user can do with the file — printing, copying text, editing. YumPDF's protect tool sets the open password.
Password best practices
Use at least 12 characters combining uppercase, lowercase, numbers, and symbols.
Never include the recipient's name, the company name, or any obvious dictionary word.
Share the password through a different channel to the PDF — send the file by email, the password by SMS.
Use a password manager to store it — never rely on memory for passwords protecting important documents.
Set an expiry reminder: once the document's purpose is served, remind yourself to revoke access or destroy copies.
FAQ
Can I protect a PDF without Adobe Acrobat?
Yes. YumPDF applies the same AES-256 encryption as Acrobat, entirely in your browser. No software purchase needed.
What happens if I forget the password?
There is no recovery mechanism — that's what makes the encryption effective. Use a password manager to store the password securely.
Can I remove the password later?
Yes. Use the Unlock PDF tool — you'll need to enter the correct password to remove protection.
Protect your PDF now — free, AES-256 encrypted.
Your file never leaves your browser. No account needed.
Add Password Free