Add one PDF to protect with a password
Whether you're sending a contract, sharing financial statements, or protecting a personal document, keeping a PDF out of the wrong hands matters. I7 Pixel's password lock tool gives you real AES-256 encryption — instantly, with no server involved.
From upload to download in four straightforward steps.
A little know-how on how PDF password protection actually works goes a long way toward keeping the right documents secure without locking out the people who need them.
PDF encryption supports two independent passwords. The open (user) password is required just to view the file at all — without it, the PDF won't open in any reader. The permissions (owner) password works differently: anyone can open and read the document, but actions like printing, copying text, or editing stay locked unless that password is entered. You can set one, both, or neither, depending on how much control you need.
AES-256 is a symmetric encryption standard used by governments, banks, and enterprise software to protect sensitive data. Applying it to a PDF means the file's contents are scrambled at a mathematical level that's computationally infeasible to break by guessing — the only practical way in is the correct password. This is a meaningfully stronger guarantee than older, weaker PDF encryption schemes still found in some legacy tools.
Encryption strength only matters if the password itself is strong. Aim for at least 12 characters mixing upper and lowercase letters, numbers, and symbols, and avoid names, dates, or dictionary words. Use the strength meter in the tool as a guide, and store the password somewhere safe — separately from the PDF itself — since encrypted PDFs generally cannot be recovered without it.
Quick guide to what happens when you toggle each permission off.
| Setting | What It Controls | Typical Use |
|---|---|---|
| Open Password Popular | Required to view or open the PDF at all | Confidential contracts, financial statements, private records |
| Permissions Password | Required to unlock printing, copying, or editing | Documents you want widely viewable but not freely reused |
| Printing | Whether the PDF can be sent to a printer | Ebooks, drafts, or documents meant for screen-only viewing |
| Copying | Whether text and images can be selected and copied out | Protecting original writing, research, or proprietary content |
| Editing Popular | Whether the file's content can be modified | Signed contracts, final reports, official forms |
A locked PDF makes the difference between a document you control and one that's freely copied or altered — this tool covers every common scenario.
Answers to the most common questions about locking PDFs with this tool.
Yes — completely free. There are no limits, no accounts, no watermarks, and no charges. Lock as many PDFs as you need.
No — never. All encryption happens locally using JavaScript in your browser. Your PDF and its contents never leave your device, so sensitive documents stay completely private.
The tool applies AES-256 encryption, the same industry-standard level of protection used by professional PDF software, directly in your browser.
An open (user) password is required just to view the PDF. A permissions (owner) password lets anyone open the file but restricts actions like printing, copying, or editing unless that password is entered.
Yes. Set only a permissions password and leave the open password blank — anyone can view the PDF, but printing, copying, and editing stay restricted unless the permissions password is provided.
No. Encryption only adds a security layer around the file. Text, images, formatting, and page count remain exactly as they were in the original PDF.
Tried the tool? Leave a quick rating and help others find it.
All tools at I7 Pixel run in your browser — no uploads, no accounts, always free.