Protect a PDF

Secure your PDF with a password — 128-bit encryption, server-side processing.

Protect a PDF →

How to protect a PDF

  1. Click "Protect a PDF"
  2. Drag and drop or select your PDF file
  3. Choose the Protect option from the output list
  4. Enter your desired password
  5. Download your encrypted PDF

Frequently asked questions

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.

Can I protect an already-protected PDF?

You will need to unlock it with its current password before re-protecting it.

Does CoreConverter store my password?

No. The password is never stored — it is used only during processing, in memory.

What encryption level is used?

The PDF is encrypted with RC4 128-bit via qpdf, compatible with all modern PDF readers.