What encryption does letsgoPDF use?

AES-256 — the same standard used by banks, defence, and PDF readers since PDF 2.0. Without the password, the file content is unreadable even by our servers (we never see the password).

Is the password recoverable if I lose it?

No. AES-256 is mathematically infeasible to brute-force in any reasonable time. If you lose the password, the file is gone. Use a password manager.

Does the recipient need special software?

No. Every modern PDF reader (Acrobat, Preview, Foxit, browser PDF viewers) prompts for the password automatically.

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Password protect a PDF — AES-256, in your browser.

Add a password to any PDF. The file is encrypted with AES-256 — the same algorithm used for banking and government data. Anyone opening the PDF will need the password before they can see a single page.

Add a password All PDF tools

How it works

Drop the PDF onto letsgoPDF. Pick Protect.
Type the password you want recipients to enter. Use something memorable but not trivial — 12+ characters with letters, numbers, and a symbol is solid.
Click Apply. The PDF is encrypted and downloaded. Save the password somewhere you'll find it — there's no recovery.

When to password-protect a PDF

Medical / financial records. Sharing tax returns, medical bills, or bank statements with an accountant or advisor.
Legal documents. Contracts, NDAs, employment paperwork in transit.
HR documents. Pay slips, offer letters — any HR document where the recipient mailbox or shared drive isn't secure.
Personal IDs. Scans of passports, driver's licences, ID cards. Pair with our Smart Redact for sensitive bits you don't want to share at all.

Picking a strong password

Length over complexity. A 16-character passphrase like red-brick-coffee-tuesday is harder to crack than P@ssw0rd!.
Don't reuse passwords. If the recipient's email leaks, your reused password leaks with it. Generate a unique one per file.
Send the password through a different channel. If the PDF is sent by email, send the password by SMS or a messaging app. Putting both in the same email defeats the protection.

Common questions

Will recipients need to install anything?: No. Every modern PDF reader (Acrobat, Apple Preview, Foxit, Edge, Chrome's built-in viewer) handles password-protected PDFs natively.
Can I remove the password later if I forget it?: No. Password removal needs the original password — we can't unlock files we never had keys for. Save the password somewhere safe.
Are my files uploaded?: Protect uses ConvertAPI as a backend (encrypted in transit, deleted after). The password is sent over HTTPS only and not retained.
Can I set permissions (no print, no copy) instead of a full password?: Owner-permissions-only protection is on the roadmap. For now, the action sets a user password (open password). That's the strongest of the two.

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