Protect PDF

Add a password to a PDF so only the people you share it with can open it.

We never store passwords
No watermark on downloads

or drop your file here

Strong PDF Encryption

Your PDF is encrypted with AES-256, and only the password can open it.

Protect on Any Device

Works in any browser on Mac, Windows, Linux, iPhone and Android. No install.

Then Add a Watermark

Mark protected files CONFIDENTIAL with Add Watermark as a visible warning.

Three Steps to a Secure PDF

Password protect a PDF in three steps, no software to install, no account needed.

Upload your PDF

Drag and drop or select your confidential file up to 600MB on the free plan and 5GB on paid.

Set your password

Type in a strong, memorable password to lock your PDF. Make sure to save it, as lost passwords cannot be recovered.

Download the Result

Your locked PDF is ready to download immediately and auto-deleted from our servers after 15 min.

Got a stack of PDFs? Lock them all with a workflow

Keep Your Confidential Information Safe.

Email and cloud storage aren't always secure. Here is where adding a password to your PDF protects you, your clients, and your business.

Employee Payroll & HR

Secure payslips, tax forms, compensation letters, and performance reviews before emailing them to employees.

Financial Statements

Protect bank statements, profit/loss records, and sensitive accounting reports before sharing them with accountants or investors.

Legal Agreements

Lock NDAs, partnership contracts, and confidential drafts to prevent unauthorized parties from reading sensitive terms.

Medical Records

Safeguard personal health information, laboratory test results, and insurance claims to maintain privacy when transferring files.

Intellectual Property

Protect your proprietary research, unpublished manuscripts, design blueprints, or patent drafts from being leaked or viewed.

Personal Identification

Add a crucial layer of security to digitized passports, government ID cards, and tax documents on your local device or cloud.

How PDF password protection works

When you set a password, FynePDF encrypts your PDF's contents with AES-256 and rebuilds the file so it can only be decrypted with that password. The protection lives inside the file itself, so it holds wherever the document travels, email, cloud storage, a USB stick, someone else's computer.

Encrypted, not just flagged

The content is genuinely scrambled. Without the password there's nothing readable in the file, even for someone inspecting it directly.

Password stays with the file

Passwords are used to encrypt your file and then discarded. Nothing is stored, logged, or recoverable, including by us.

Choose a strong one

The cipher is only as strong as the password. The strength meter shows where yours stands; length matters more than symbols.

Before and after protecting your PDF

Unlock PDF

Remove the password later when you no longer need it.

Redact PDFAI

Permanently remove sensitive content, not just restrict access.

Sign PDF

Sign the document before locking it.

Frequently Asked Questions

What types of password protection can I add?

FynePDF adds an open password, which is required to view the document. Anyone without it can't open the file at all. A strength meter shows how secure your chosen password is as you type, and the encryption applies to the whole document rather than individual pages.

Can I set different permissions for different users?

Standard PDF encryption applies the same permissions to everyone with the password, it can't grant one person print access and deny another. Per-user permissions require DRM or certificate-based security, which FynePDF doesn't offer. For different access levels, protect separate copies with different passwords.

Is the Protect tool free to use online?

Yes, FynePDF's Protect PDF tool is free with no sign-up required. Free accounts protect files up to 600MB, with 10 tasks and 600MB of processing a day. Professional at $7/month raises this to 5GB with unlimited daily tasks.

Is it safe to use Protect on FynePDF? Are my files secure?

File transfers use TLS encryption. Cloud-processed files are automatically deleted within 15 minutes after processing completes, unless you choose to save them to your Library. Documents are not used to train AI models. Read the Privacy Policy for storage and processing details.

Can I use the Protect tool on Mac, Windows, or mobile?

Yes. FynePDF's PDF protector works directly from your browser, so it works on Windows, Mac, Linux, iOS and Android with no installation. Chrome, Firefox, Safari and Edge are all supported.

Do you store or have access to my password?

No. Your password is used to encrypt the PDF and then immediately discarded. It is not stored, logged, or recoverable by FynePDF. That also means we can't help you open the file if you lose it, so save it somewhere safe before you close the tab.

What happens if I forget my PDF password?

There's no recovery. PDF encryption is designed so the file can't be opened without the password, and no one including FynePDF can bypass it. Store the password in a password manager before you send the document. If you still have an unprotected original, protect it again with a new password.

Is password-protecting a PDF actually secure?

Yes, with a strong password. AES-256 encryption is the same standard used to protect government and banking data, and it can't be broken directly. The weak point is always the password itself, short or common ones fall to automated guessing quickly. Use at least 12 characters, and prefer a long passphrase over a short complicated one.

How do I remove a password from a PDF later?

Use Unlock PDF and enter the password you set. The unlocked copy downloads without encryption, and your protected version stays unchanged unless you overwrite it.