Lock and protect PDFs online
Add password protection to sensitive documents before you share them — contracts, financials, and personal records stay behind a passphrase you choose.
Free plan includes 20 executions of premium tool per day. No credit card required.
How to lock a PDF with DocMatePDF
- 1
Create your free account
Sign up in seconds to encrypt your PDF and download the protected file.
- 2
Upload your PDF
Drop the document you want to secure and set a strong password.
- 3
Download the locked PDF
Get an encrypted PDF that opens only with your password — safe to email or store.
Why use DocMatePDF to lock PDFs
Password protection
Keep confidential files behind a passphrase only you and your recipients know.
Private by design
Encryption runs in your browser — your PDF is not uploaded to our servers.
Share with confidence
Send sensitive documents knowing they cannot be opened without the password.
Part of a full PDF toolkit
Lock here, then watermark or compress with other DocMatePDF tools.
Frequently asked questions
- Is locking PDFs free?
- Yes. Create a free account to lock PDFs. Free plans include a daily run limit; upgrade to Pro for more runs per day.
- What if I forget the password?
- DocMatePDF cannot recover a lost password. Store it securely and share it only with intended recipients.
- Are my files stored on your servers?
- No. Encryption runs locally in your browser. We do not keep copies after you close the tab.
Related PDF tools
Ready to protect your PDF?
Create a free DocMatePDF account and add password protection in seconds.
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