🔒 PDF 保護
PDFにパスワード保護を追加 — 無料、高速、プライベート。
Drop PDF file(s) here
or click to browse
使い方 PDF 保護
ファイルを上のエリアにドラッグ＆ドロップするか、クリックして選択してください。
ボタンをクリックして、ブラウザ内で即座にファイルを処理します。
処理されたファイルは自動的にダウンロードされます。登録不要！
Performance & Details
Uses AES encryption via pdf-lib. Password is applied locally — it never touches any server. Encrypted PDFs open in any standard PDF reader (Adobe, Preview, Chrome).
All processing uses pdf-lib (open-source). Files stay in your browser — zero server uploads. Last verified: May 2026.
PDF 保護 — 全米で利用可能
PDF 保護 — Available Across Europe
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Go Pro — $5/monthPDF 保護 — Frequently Asked Questions
What type of encryption is used?▼
We apply AES encryption, the industry standard used by banks and governments worldwide.
What happens if I forget the password?▼
There is no way to recover a forgotten password from an encrypted PDF. Keep your password in a safe place.
Can I set different permissions (print, copy)?▼
Currently we support open-password protection. Advanced permission controls are on our roadmap.
Will password protection slow down the PDF?▼
No — encrypted PDFs open just as fast as regular ones, just requiring a password first.
Is this tool suitable for legal or financial documents?▼
Yes — password protection adds a strong security layer for contracts, tax documents, and financial records.