PDFtk – PDF Editing Tool



PDFtk (short for PDF Toolkit) is a cross-platform tool for manipulating Portable Document Format (PDF) documents. It comes in two versions: PDFtk Free (open source) and PDFtk Pro (proprietary paid). Many functions are not available in the open-source version, but only in the paid proprietary one.

PDFtk is a front end to the iText library (compiled to native code using GCJ), capable of splitting, merging, encrypting, decrypting, uncompressing, recompressing, and repairing PDFs. It can also be used to manipulate watermarks, metadata, and to fill PDF Forms with FDF Data (Forms Data Format) or XFDF Data (XML Form Data Format).
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PDFtk,全稱PDF Toolkit,是一個在命令行運行的跨平台工具,用作處理PDF文件。





If you use LibreOffice and export a document as .pdf file there’s the option to set a password:

File -> Export as PDF
Entering Passwords
-> OK
-> Export

PDF Options
Security -> [Set Passwords …]