PDFThings

Protect a PDF Free

Protect a PDF free — genuinely free. No credit card, no trial countdown, no watermark on your output. Add or remove password protection from PDF files.

Drop a file here, or browse

PDF,APPLICATION/PDF

Most “free” PDF tools aren't really free — they cap file sizes, count your jobs, or stamp a watermark on the result. This one has none of those limits: protect up to 20 PDFs per job, as often as you like, with clean output every time.

The tool is funded entirely by optional premium plans for heavy users. For everyday protecting, the free tier is all you need.

Why use this merger

Truly free

No credit card, no trial clock, no hidden charges. Process as many documents as you need.

No watermarks

Your output is clean. We never stamp a brand or promotional watermark onto your files.

No file-size tricks

Works with real-world documents, not just tiny test files.

No account walls

Free protecting without registration. Upload, protect, download, and close the tab.

How to protect a pdf free

  1. 1

    Upload your PDF

    Select the PDF you want to protect or unlock.

  2. 2

    Choose protect or unlock

    Pick protect to add a password, or unlock to remove one (you'll need the password).

  3. 3

    Run and download

    Download the protected or unlocked PDF.

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Frequently Asked Questions

Is the free protect really unlimited?
Free protecting lets you process up to 20 PDFs per job per job with no watermark and no daily quota.
Will you watermark my output?
No. Your files come out clean, with no branding added.
Why is it free?
The free tool is supported by optional premium plans. Regular use costs nothing.