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Decrypt PDF

Remove the open password or permission restrictions, output an editable file.

UnlockRemove password
點選或拖拽 PDF 到這裡
上传已加密或有權限限制的 PDF

💡 僅支援已知開啟密碼的 PDF,或只設定了「權限限制」(禁止列印 / 編輯)的檔案。解鎖後文字可能轉為圖片,無法再選中複製。

How to use

This tool belongs to the “Watermark & optimise” category.

  1. 1Watermarks can be text or image: text takes content, font, size and colour, while an image watermark can be tiled or angled.
  2. 2Page numbers support Page {num}, {num} / {total} or a bare number, with font, size, footer and side margins, and mirrored odd and even pages.
  3. 3Compression trades image sharpness for size. Try one level first: text-only PDFs shrink little, scanned ones shrink a lot.

Every PDF is handled in this tab by JavaScript. Files never leave your device and we keep no copy.

Frequently asked questions

Can I watermark or compress a protected PDF?

Sort out permissions first: "Decrypt PDF" works only on files whose open password you know, or on files that merely restrict printing and editing.

Does compression hurt quality?

It does - it re-encodes the images inside the page. Run the heavier setting to see the result, then back off if it is too aggressive.

Text became unselectable after decrypting.

That is expected: unlocking can convert the text layer into an image. If you need searchable text, run OCR over the result.