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Add real password protection, entirely in your browser
Large files (over 50 MB) may take longer or run out of browser memory
About Add PDF Password
Adds a password to a PDF with AES-256 encryption, the strongest standard the PDF format offers, so the file asks for the password before it opens in any current PDF reader. Your pages, bookmarks, form fields and links stay as they were. Everything happens in your browser; the file is never uploaded.
Drop a PDF, type the password twice and click Protect PDF. The tool then opens the protected file with your password to check that it works, and shows the result before you download. Optionally block printing, copying or editing (readers are asked to respect this; the password is what keeps people out). To protect several PDFs with one password, switch to Several files (up to 5 at a time on the trial, counted as one use).
Write the password down somewhere safe: there is no way to recover it. Letters with accents and other alphabets work. Very old PDF readers from before 2006 may not open AES-256 files; every current reader, browser and phone does.
Watch: Add PDF Password in Action
- How strong is the password protection on this?
- It uses AES-256, the strongest encryption standard the PDF format offers. How hard the file is to open then depends on your password: a long, unique one is far stronger than a short or common one, so the tool rates your password as you type.
- How do I know the password actually worked?
- The tool checks it for you. After protecting, it opens the new file with the password you typed and compares the page count, title and form fields with your original, and shows "Checked: opens with your password" before you download. You can still open the download in any PDF reader to see the password prompt.
- Will every PDF reader open it?
- Every current reader, browser and phone opens AES-256 files, and passwords with accents or other alphabets work. Only very old readers from before 2006 may not.
- Can I remove a password from a PDF that already has one?
- Not with this tool — it only adds protection to a file that doesn't have it yet. There's currently no "unlock" mode for removing an existing password, even if you know it.
- What happens if I forget the password I set?
- There's no recovery option — the password is genuinely required to open the file, with no backdoor or reset. Write it down somewhere safe before you close this tab; a forgotten password means the file is permanently inaccessible through normal means.
- Is my password sent anywhere?
- No — encryption runs entirely in your browser, including deriving the encryption key from your password. Neither your file nor your password ever reaches a server.
- Can I protect a PDF that's already password-protected?
- Yes. If the PDF already has a password, you'll be asked for it when you add the file — it's unlocked in your browser first, and then the new password you choose is applied.
- Does the password protect against editing, or just opening the file?
- Just opening — this sets a password required to view the document's content at all. It doesn't separately restrict printing, copying, or editing once someone has the password and the file is open.
- What encryption does it use?
- AES-256, applied to the whole document with the password you choose. A reader must be given that password before it shows the pages. Very old PDF software may not support this level, whereas current browsers and readers do.
- What happens when I tick the block options?
- A random owner password is generated and never shown, and the permissions you picked are set as flags. Readers are asked to refuse printing, copying or editing. The password you typed is still the one that opens the file.
- Can you recover my password if I forget it?
- No. Nothing is stored anywhere and there is no reset, because the encryption depends on the password itself. Keep it in a password manager and keep the unlocked original.
- What is the Checked line after protecting?
- The tool opens the result with your password in the browser's PDF reader and compares it with the original: page count, title and form field names must match. If the check fails, the file is not offered. The line reports pages, size and AES-256.
- Does it hide the file name or remove metadata?
- No. The file keeps its name and size, and the tool does not strip title or author before encrypting. Only the document content is protected, so rename the file or clean its properties yourself if those details are sensitive.
How to use Add PDF Password
Type the password twice, first in Password to require and then in Confirm password. At least 6 characters are needed, the eye button shows or hides both fields, and a bar rates the entry from Weak to Strong. A note appears if the password starts or ends with a space, because spaces count.
Under Also ask readers to block, you may tick Printing, Copying text or Editing. Protect PDF stays disabled until the two entries match. After you press it, the tool reopens the new file with your password and compares page count, title and form fields with the original, then shows a green Checked line. Download the file ending in -protected.
When to use it
Emailing a payslip, medical letter or tax form to one person, keeping a scan of an identity document on a shared drive or phone, or sending a draft contract whose contents should stay unreadable to anyone who intercepts the attachment. It also suits a document parked in cloud storage you do not fully control.
When not to use it
It does not hide that a document exists, since the file name and size stay visible. To blank out particular names or numbers before sharing, redact them with Redact PDF instead. If recipients must open the file without typing anything, a plain share link is simpler, and to label a file rather than lock it, PDF Watermark does that.
Tips for best results
Choose a long phrase rather than a short word; the strength bar is a quick guide and its list of common passwords is short. Pass the password on through a different channel than the file. The block options are only requests that well-behaved readers honour, so treat the password as the real lock. Keep the unlocked original somewhere safe, because the tool never changes it.
Limitations
The encryption is AES-256 with a required password to open. Printing, copying and editing limits are flags that a reader may ignore. File name, file size and the fact that it is a PDF stay visible, and metadata such as title and author is not removed. A lost password cannot be recovered, and an already encrypted PDF cannot be loaded here. Several files at once: the Several files switch protects up to 5 PDFs on the trial (more on a paid plan) with the same password and counts as one use; each result is opened with the password to check it before it is offered.
Privacy
Encryption runs in your tab with a PDF library that comes with the page, and the password lives only in the two fields you typed it into. The follow-up check opens the protected copy locally with the browser's PDF reader. Neither the document nor the password is sent to a server, so the site has nothing to reset or recover.
Next: Add Watermark
Mark it confidential or draft, if that applies
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