Protect PDF with Password Free - Encrypt PDF Online | DesiDocs
Add password protection to any PDF in seconds. Free online PDF encryption with no watermark and automatic file deletion.
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Putting a password on a file you are about to send
Anything you email is one forwarded message away from an audience you did not
choose. A salary slip, a contract draft, a scanned ID, a set of accounts —
encrypting the PDF means the file is useless to anyone who does not have the
password, including anyone who ends up with it by accident.
AES-256, not a "please do not open" flag
There are two very different things sold as PDF protection. One sets a flag
asking viewers to restrict printing or copying, which any competent tool
ignores. The other encrypts the file's contents so it cannot be rendered at all
without the key.
DesiDocs does the second, with AES-256 — the strongest encryption the PDF
specification defines, and the same standard used for full-disk encryption. The
document is unreadable without the password rather than politely marked
read-only.
Choosing a password that is worth having
The encryption is only as good as what you pick, and AES-256 protecting a
password of 123456 protects nothing. Use something long, and send it to your recipient
by a different route than the file — the password in the same email as the
attachment defeats the purpose entirely. A phone call or a message is fine; the
same inbox is not.
Keep your own copy of the password somewhere you will still have it in a year.
DesiDocs cannot recover it. If you lose the password to a file you encrypted,
that file is genuinely gone, which is what makes the encryption worth using.
Limits and privacy
25 MB per file. To take a password back off a document, use
Unlock PDF. Your upload, your password and the encrypted result
are never stored — the password is used once in memory, and the files are
deleted within 30 minutes. Free, no account, no watermark.
How it works
- Upload PDF — Select the PDF you want to protect.
- Set a password — Choose a strong password for the document.
- Download — Download your encrypted, password-protected PDF.
Frequently asked questions
How do I password-protect a PDF?
Upload your PDF, choose a password, and download the encrypted file. Anyone opening it will need the password.
What encryption is used?
Your PDF is protected with standard AES encryption supported by all major PDF readers.
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