Where the locked file opens
In Adobe Acrobat and Reader, Preview on a Mac, Chrome, Edge and Firefox, and the PDF apps on iPhone and Android. Only very old PDF programs that don’t know AES-256 will fail.
Password protect a PDF
Password protect PDF documents in under a minute: only people who know the password can open the file. The document and the password stay with you; we never receive them.
or drop a file anywhere on this page
One PDF file, any size
Your privacy comes first
Your contracts, passport scans and family videos stay yours. No one but you gets to see them.
We never store your files
They don’t even reach us: your phone or computer does the work. Nothing to delete later.
100% free
No daily limits, no file-size cap, no paid Pro plan.
No sign-up
No account to create, no email to give. No account, nothing to hack.
How it works
- Open a PDFPick the document you want to lock.
- Set a passwordType it twice, so a typo can’t lock the file with the wrong one.
- Save the locked copyPress Save. The new PDF asks for the password every time it opens.
What changes when you password protect PDF files
The file is encrypted with AES-256, the strongest cipher the PDF standard offers. Without the password the pages are not hidden but scrambled into bytes nobody can read. The encryption runs in your browser.
Pick a password that holds
- Length beats cleverness: three or four unrelated words are easy to remember and hard to guess.
- Don’t reuse the password of your email or your bank.
- Case matters: “Cat” and “cat” are two different passwords.
- Send the password another way: the PDF by email, the password by text or a call.
A forgotten password can’t be recovered
There is no back door and no reset link, for us or anyone else. Keep the password in a password manager, or keep an unlocked copy where only you can reach it.
Protect a PDF from copying and printing
Printing and copying text are allowed by default. Turn off Allow printing or Allow copying text, and the file asks viewers to block it. Most viewers obey and some ignore it. Only the open password truly locks the document.
What a password doesn’t do
It doesn’t hide the file name or its size. Anyone who opens the PDF with the password can forward it or take screenshots. If the receiver needs only part of the document, remove the rest first with Redact PDF or Split PDF.
Good to know
- Pages, text and pictures stay as they were; only the lock is added.
- A PDF that already has a password must be unlocked before you set a new one.
- To remove the password later, use Unlock PDF.
Free, fast and all yours
Free forever
Every tool is free and will stay free. No trial, no ads, no paid plan.
No sign-up, no login
Open the page and start. No account, no email, no password.
Instant
Nothing to upload and no queue: a video opens in a second, a simple trim saves in seconds.
No file size limits
We set none. A file can be as big as your device can handle.
No watermarks, no copyright
No logo on top and no rights claimed: what you make is 100% yours.
Made for phones too
The same tools on iPhone, Android and a computer, with big buttons and plain words.
Questions
Yes, attach it like any other file. Send the password separately, not in the same email.
There is no separate edit lock here. Without the password the file can’t be opened, so it can’t be changed either. Anyone who has the password can edit it.
Yes, if the password is strong. A short or common password is the weak point, not the encryption.
Unlock it with the current password in Unlock PDF, then lock the copy here with the new one.
Barely. Encryption scrambles the content but adds almost nothing to the size.
Open this page in Safari, choose the file from Files, type the password twice and save. The locked copy lands in Downloads.
One file at a time. To lock several documents with one password, combine them first with Merge PDF.