Lock PDF
Add an open password to a PDF in your browser. Choose a password, confirm it, preview the first page, then download a protected copy. Already encrypted files are not re-locked here. Nothing is uploaded.
or drop files here
Runs in your browser. Nothing is uploaded.
How it works
Drop an unlocked PDF
Choose a PDF up to 10 MB that is not already password-protected. The file stays in this tab.
Set and confirm a password
Enter an open password of at least 4 characters and confirm it. Viewers will need this password to open the downloaded file.
Lock and download
Tap Lock PDF to create a protected copy. Keep the password somewhere safe; Easy24 cannot recover it.
What is Lock PDF?
Lock PDF password-protects PDF files in your browser before you share them. It is meant for open-password protection, not for secret redaction or cracking other people’s files.
Why use this tool
- AES-256 open-password protection in the browser
- Password confirmation and show/hide toggle
- First-page preview for unlocked source files
- Clear rejection of already encrypted PDFs
- Private local processing. Free: 5/day, 10 MB
- Pairs with Unlock PDF for restriction removal when supported
Questions
What does Lock PDF do?
It adds an open password to an unlocked PDF so apps ask for that password before showing the pages. Processing stays in your browser.
Can I lock a PDF that already has a password?
Not in this tool. Unlock it first with Unlock PDF when possible, then lock again with a new password.
Is this the same as redacting secrets?
No. Anyone with the password can read the full document. To hide content permanently, remove or redact it instead of only encrypting.
Which password strength is used?
The tool writes modern AES-256 open-password protection. Use a unique password you will remember.
Are my files uploaded?
No. Scanning, preview, and encryption stay on your device.
Is there a daily limit?
The free plan allows 5 locks per day with files up to 10 MB. Preview does not use the daily quota.
Why do I need HTTPS?
Browser crypto for AES-256 requires a secure context. Localhost and HTTPS sites work; plain HTTP usually does not.
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