Open alternatives5
Open-source apps that replace Adobe Acrobat
Stirling PDF is a tool for editing, signing, redacting, converting and merging PDF files. It can run as a desktop app, in a web browser, or on your own server so documents stay on your own machines.
OffPDF is a free desktop app for Windows and Mac that edits, annotates, fills in, signs, merges, splits, converts, compresses and OCRs PDFs. It is for people who want to do this work on their own computer without uploads or accounts.
Xournal++ is a desktop app for taking handwritten notes with a pen or stylus, and it can also be used to mark up PDFs. It is for people who want to write, draw and annotate notes on a computer, with an Android version also available.
PDF Arranger is a desktop app for merging, splitting, rotating, cropping and rearranging the pages of PDF files through a visual interface. It is aimed at people who need to tidy up or combine PDF documents.
Okular is a document viewer for reading PDFs and other document formats on a computer. It is aimed at people who need to read and annotate documents.
What's missing
What people still miss here, and wish existed. Upvote what matters to you.
Before you build
Planning something for PDF tools? See what exists first, so you can reuse parts or explain what's different. Paste this into any AI assistant:
Fix the list itself
A project or closed app missing from this list, or a mistake on it? These open a short form on GitHub, and a mod reviews it. To say what a project can't do, use What's missing.
About this page
Replaces fully means it does the main job of these apps; Replaces partly means it covers some of it.
Licenses: every project here uses an open-source license (what each one means). Open core means some parts are paid or under another license.
GitHub stars are shown for reference. They measure popularity, not whether it replaces anything.
Verified means r/TrueOpenSource mods checked it: open-source license, maintained, and it really does the job.
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