Encrypt PDF

Lock your PDF by adding a password.

Click to select a file or drag and drop

Most file processing happens in this browser.

Practical guide

Encrypt PDF

Lock your PDF by adding a password.

Guide updated August 2026

What this tool does

Encrypt PDF manages document passwords, permissions, metadata, layers, or embedded files.

Useful for

  • Require a password before opening a document.
  • Protect a file before sending it.
  • Set owner controls for compatible readers.

A reliable workflow

  1. Choose the source file and confirm that it opens correctly before processing.
  2. Review the available options. Start with the defaults, then change only the setting that affects your intended result.
  3. Process the file, open the result, and verify page order, text, images, links, and forms before replacing your original.

How your document is handled

Document contents are processed in your browser and are not uploaded to an AmrrkPDF application server. Your browser still downloads the application code and required runtime assets when needed.

Limits and compatibility

PDF permission flags are respected by compliant readers but are not a substitute for strong encryption. Removing hidden data can also remove useful document features.

If the result is not what you expected

If the operation fails, confirm the correct owner password and keep an untouched backup. Signed documents can become invalid after any structural change.