# Encrypt PDF Online

> Encrypt PDF online for free — password-protect in your browser. Private, no signup, no watermarks. We never see the file or password.

Canonical: https://mypdf.space/tools/encrypt-pdf
Last updated: 2026-10-26

## Short answer

Encrypt PDF runs entirely in your browser. Password-protect a PDF so it cannot be opened without the password. No account, no watermark, and the file never leaves your device.

## About this tool

Password-protect a PDF so it cannot be opened without the password.

Password-protect a PDF so it cannot open without the password — free and local.

Encrypt PDF online for free — password-protect a file so it cannot be opened without the password. Encryption uses standard PDF crypto in your browser — we never see the file or password. If the file is already encrypted, unlock it first, then encrypt again with the password you want recipients to use.

## How to use

1. Open an unlocked PDF.
2. Set a password you will remember.
3. Encrypt and download the protected file.

## What you need

- An unlocked PDF
- A password you will remember

## Notes

- Uses standard PDF encryption locally.
- If the file is already encrypted, unlock it first, then encrypt again.

## Use cases

- Protect a confidential PDF before emailing it.
- Add an open password after redacting sensitive pages.
- Students or freelancers locking drafts before sharing externally.

## FAQ

### Where does encryption run?

On your device. We never receive the file or the password. If the file is already encrypted, unlock it first.

### Is encrypt PDF free?

Yes — free, no watermark, no account.

### How should I share the password?

Send the password on a different channel from the file — a phone call or chat, not the same email thread.

## Related

- [Unlock PDF](https://mypdf.space/tools/unlock-pdf)
- [Confidential Send](https://mypdf.space/tools/workflow)
- [Remove metadata](https://mypdf.space/tools/remove-metadata)
- [Watermark](https://mypdf.space/tools/watermark)
- [Redact](https://mypdf.space/tools/redact)
- [Privacy scanner](https://mypdf.space/tools/privacy-scanner)
- [Category](https://mypdf.space/security)