Password protect PDF

Client

Add a password required to open the document—processing stays in your browser. More PDF tools on the PDF hub.

About Password protect PDF

Encrypt a PDF with a user password in the browser—AES protection, no server upload. The interactive transform on this page runs in your browser tab—Toolcore does not need your paste for the core operation described above.

How to use this page

Paste or type in the main workspace, run the primary action from the toolbar, then copy or download the result. Use Load example when the page offers it, or URL prefill (?q= / ?qb=) so agents and tickets open the same input.

Add a password required to open the PDF. Processing runs in your browser; passwords are not sent to Toolcore servers.

Max 25 MB. Uses AES encryption via pdf-lib-with-encrypt in-browser.

Nearby workflows on Toolcore

  • PDF info — Inspect page count, metadata, and encryption status—processing stays in your browser. after you download or inspect a PDF on this page.
  • Merge PDF — Combine multiple PDF files in order—one download; processing stays in your browser. after you download or inspect a PDF on this page.
  • Compress PDF — Best-effort PDF shrink by re-saving in the browser—not server OCR or Ghostscript; see size before/after. after you download or inspect a PDF on this page.
  • PDF watermark — Add diagonal text to every PDF page in the browser—download a labeled copy without upload. after you download or inspect a PDF on this page.

Common use cases

  • Lock a contract PDF before email when desktop tools are unavailable.
  • Add an open password to exports from merge or split workflows on this site.
  • Test that recipients can open with the password you chose—passwords stay in your tab only.

Common mistakes to avoid

  • Losing the password

    There is no recovery—store the password in your password manager before sharing the file.

  • Expecting permission-only PDFs

    This tool sets encryption required to open. Owner-password permission flags are not customized here.

FAQ

Is the PDF uploaded?

No. Encryption runs with pdf-lib-with-encrypt entirely in your browser.

Can I remove a password here?

Not on this page—use desktop tools or unlock elsewhere, then re-export without encryption.

What encryption is used?

The library applies standard PDF password security (AES) compatible with common PDF readers.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • password protect pdf online
  • encrypt pdf in browser no upload
  • add password to pdf free
  • pdf aes encryption local

More tools

Related utilities you can open in another tab—mostly client-side.