Free PDF tool

Lock a PDF
with a password

Add password protection to any PDF in one click. AES encryption, runs on the same engine that powers PDF Generator API in production. No signup, no email, no upsell.

Free, no signup
Files deleted after processing
Encrypt PDF Step 1 of 3
Choose a password
8 to 128 characters. Mix letters, numbers and symbols for a stronger password.
  1. 1Drop in any PDF, up to 25 MB.
  2. 2Choose a password. We use AES encryption to lock the file.
  3. 3Download the encrypted version. The recipient enters the password to open it.
Encrypting your PDF…
Applying AES encryption to the document.

Files don't stick around

Uploads are deleted after the request. We don't store your documents, and we never look at them.

Same engine as production

Powered by PDF Generator API, the same infrastructure trusted by 2,000+ developers worldwide for high-volume document workflows.

Need to do this at scale?

If you're stamping hundreds of PDFs a day, hit the API directly. Same options, programmatic, fits in any backend in five minutes.

Ready to automate?

Encrypt thousands of PDFs without lifting a finger

PDF Generator API gives you optimization, watermarking, encryption, form filling and more, all through one clean REST API. Free 14-day trial, no credit card.

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