The best open source alternative to Nitro PDF is PDFsam Basic. If that doesn't suit you, our users have ranked more than 100 alternatives to Nitro PDF and 19 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Nitro PDF are PaperKnife, Skim, LibreSign and PDF4QT.
PDFsam Basic is a free and open-source desktop application for splitting and merging PDF files. It runs entirely on your own computer, so your files are never uploaded anywhere and it works fully offline.
Italy
EU
Privacy-first PDF utility (Zero-Server Architecture). Merge, split, compress, and edit PDFs 100% locally on your device. No uploads, no servers, no tracking.
PDF viewer for macOS supports scientific papers, annotations, highlights, bookmarks, split view, exporting notes, AppleScript, multiple annotation types, bibliography integration, full-screen, search, and compatibility with various macOS versions.
LibreSign is a web application for electronic signatures (e-Sign) that offer the possibility of signing documents online with security and agility.
Open-source PDF viewer and editor using Qt framework, featuring hardware-accelerated rendering, encryption, multithreading, text-to-speech, annotation tools, form filling, high-res monitor support, document compression, audio book conversion, and signature validation.
CzechiaEU
Free (and open source) editor for manipulating PDF documents. GUI version + commandline interface. Scripting is used to a great extent in editor and almost anything can be scripted, it is possible to create own scripts or plugins.
A feature-rich, privacy-focused PDF app built with Jetpack Compose and Material 3. View, edit, and manage PDFs with 12 powerful tools including merge, split, compress, rotate, lock/unlock, and more. Supports bookmarks, table of contents, full-text search, and auto-scroll for...
Bangladesh
CubePDF Utility allows you to intuitively perform editing tasks such as merging, extracting, splitting, deleting, reordering, and rotating PDF pages via thumbnails.
Japan
Privacy-first, offline PDF editor for Android. Merge, split, compress, convert and annotate PDFs — 100% on-device, no internet required.
India
Converts PDF files into Word, Excel, PowerPoint, HTML, ePub, and diverse image formats using advanced OCR technology, ensures accurate preservation of layout and structure, supports batch and partial page conversions, and handles multilingual and scanned documents.
Hong Kong SAR China
PoDoFoBrowser is a graphical browser and editor for the object structure of PDF files.
CubePDF Page is a Windows software that allows you to easily merge and split PDF files. It is very simple to use, just Drag&Drop PDF files and click the Merge or Split button. In addition to PDF files, images can also be merged as PDF pages.
Japan
