This content originally appeared on DEV Community and was authored by xidiri
Ever needed to combine multiple PDF files — but didn’t have Wi-Fi? Or maybe you didn’t feel great about uploading sensitive docs to random online converters?
Same here.
That’s why I went down the rabbit hole of free, offline PDF merge tools that work without internet, without watermarks, and without paywalls. After hands-on testing, here are the best picks for 2025 — perfect for devs, students, or anyone who values speed, simplicity, and privacy.
Why Merge PDFs Offline?
Privacy-first: Keep your files local. No uploads = no leaks.
Faster: Zero wait time. Merge instantly.
No file limits: Most online tools cap file size or number of pages.
Works anywhere: Offline-ready — even on a plane or remote site.
Tried-and-Tested Tools That Work in 2025
PDFsam Basic
Free & open-source
Cross-platform (Windows, Mac, Linux)
Drag-and-drop UI, great for batch merging
Zero watermark, no ads or nags
LibreOffice Draw
Part of the LibreOffice suite
Insert PDF pages, reorder, and export as PDF
Especially good if you already use LibreOffice
PDF Arranger
Lightweight GTK-based app (Linux & Windows)
Visual merging, reordering, rotating
Open-source and surprisingly powerful
PDF-XChange Editor
Only for Windows, but incredibly feature-rich
Merge via File > New Document > Combine Files
Steeper learning curve, but precise and reliable
Sejda PDF Desktop
Offline version of the popular web tool
Free tier includes basic merging
No watermark, no tracking, no problem
How to Merge PDFs Offline (In 4 Steps)
Open your chosen tool (e.g., PDFsam or PDF-XChange)
Add your PDF files
Reorder them as needed
Click Merge or Export — boom, done.
No ads. No internet. No shady redirects.
Offline vs Online PDF Merging Tools
FeatureOffline Tools Online Tools 
Internet Needed
No YesFile Size Limits Rarely Often capped (e.g., 50MB)Watermarks None (with right tools) Yes (free plans)Security
Local-only
Cloud-based risks
Real-World Use Cases
Merging invoices at a client’s site with no Wi-Fi
Combining multi-page design specs during dev sprints
Offline handling of NDAs, contracts, or legal doc
Pro Tips from Experience
Use LibreOffice Draw if you need to tweak text inside PDFs
Go with PDFsam for batch merging tons of files
Try PDF-XChange Editor for advanced control and formatting
Final Though
You don’t need cloud tools to merge PDFs. In fact, going offline gives you better speed, security, and freedom — especially in 2025 where bloated web apps are the norm.
Whether you’re managing paperwork on a deadline or just avoiding sketchy upload sites, these tools just work. I’ve used them for client docs, project notes, and even tax files — never looked back.
Full walkthrough + screenshots on FreeToolVerse
Read the full guide →
Coming Up Next:
Split PDF Files Offline — Free Tools That Get It Done 
Follow for more no-fluff, privacy-friendly tool guides.
This content originally appeared on DEV Community and was authored by xidiri