Upload a PDF and set a password so it can't be opened without it. Everything happens inside your browser your file and your password are never uploaded to a server. 100% free, unlimited use, no watermark.
Password protecting a PDF means encrypting the file so that a password is required before any PDF reader will open it. Unlike a simple restriction lock, this is a genuine open-password: without it, the document's content stays completely inaccessible.
This is the opposite of unlocking a PDF. Where an unlock tool removes restrictions from a file, protecting a PDF adds a real barrier that keeps unauthorized readers out entirely, useful for contracts, financial statements, personal records, and anything else you don't want opened by just anyone who gets hold of the file.
Add a real open-password to a PDF without installing software or creating an account. Everything runs locally in your browser using JavaScript, so your file and your password stay private.
Your PDF and password are processed entirely on your device. Nothing is uploaded to any server.
Most documents are protected in a few seconds, right in your browser tab.
No subscription, no watermark, no file limits, and no signup required.
Use it on desktop, tablet, or mobile in any modern browser.
Adding a password to a PDF takes less than a minute. Follow these steps:
Drag and drop your PDF file into the upload area, or click to browse your device.
Type your password twice to confirm it, then keep it stored somewhere safe.
Press "Protect PDF" the tool encrypts the file locally in your browser.
Click "Download Protected PDF" to save your password-locked document instantly.
There are many PDF protection tools online here is why people choose the NexaTools browser-based tool:
100% PrivateYour PDF and your password never leave your device. There is no server upload involved.
Completely FreeNo credit card, no hidden fees, no premium tier. Unlimited protection.
Instant ResultsNo waiting in a queue and no email verification needed to download.
Real Open-PasswordThe resulting file genuinely requires the password to open in any compliant reader.
No WatermarkYour protected document is clean, with no branding added to the file.
Works on MobileFully responsive on desktop, tablet, and mobile browsers.
When you upload a PDF and type a password into the tool above, both are handled directly by your browser using JavaScript running on your device. At no point is the file or the password sent across the internet to a remote server or stored in any database. Once you close or refresh the tab, everything is simply gone from memory nothing is retained on our end, and nobody but you ever knows the password you chose.
Adding a password is simple, but a few tips help you avoid losing access to your own file:
Since there is no recovery option, pick something memorable or save it in a password manager immediately.
Make sure both password fields match exactly before protecting, including capitalization and spacing.
Save an unprotected copy of the original file somewhere safe in case you need it again without a password.
If sending the protected PDF to someone else, share the password through a different channel than the file itself.
The NexaTools Protect PDF tool is built for anyone who needs to keep a document private, without installing desktop software or sharing files with a third-party server.
Business OwnersLock contracts, financial reports, and internal documents before sending them out.
Legal & HR TeamsProtect employee records, case files, and confidential agreements.
Accountants & Finance TeamsSecure invoices, tax documents, and statements containing sensitive numbers.
Students & ResearchersKeep personal notes, theses, or unpublished research private.
Freelancers & Small BusinessesProtect client proposals and deliverables before sharing them.
Privacy-Conscious UsersAnyone who prefers a tool that never uploads files to a server.
Here are a few everyday situations where password protecting a PDF comes in handy:
Add a password before sending a document over email as an attachment.
Protect pay stubs, invoices, or tax forms before sharing with an accountant.
Add a password to documents kept in shared cloud storage folders.
Lock a finalized agreement so it can't be opened or altered by unintended readers.
Running into an issue while protecting your PDF? Here are fixes for the most common problems:
The file may be corrupted, or it may already require a password to open. Remove any existing password first, then upload it again.
Re-type both password fields carefully, making sure capitalization and spacing are identical.
Very large PDFs aren't supported in-browser. Try compressing the PDF first with a PDF compression tool, then protect it.
There is no recovery option since nothing is stored on our servers. You will need to protect the original file again with a new password.
Some browsers block automatic downloads from JavaScript. Check your browser's download permissions or pop-up settings for this site.
Everything you need to know about the NexaTools free Protect PDF tool.
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Add a password in seconds free, private, and no signup required.