How to Merge PDF Files — Free & Private

Merge multiple PDF files into a single document directly in your browser using pdf-lib. No file leaves your device at any point — zero-server processing means your documents are never uploaded, stored, or analyzed. Works fully offline after the first page load.

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  1. Open the Merge tool

    Navigate to the PDF Merge tool. No account or login is required.

  2. Add your PDF files

    Drag and drop two or more PDF files onto the file tray, or click to browse. Files are loaded into browser memory only — nothing is sent to a server.

  3. Reorder pages if needed

    Drag thumbnails to rearrange the page order. You can also delete individual pages before merging.

  4. Download the merged PDF

    Click 'Download Merged PDF'. The combined file is generated locally and saved directly to your device. File memory is cleared automatically afterwards.

Open Merge Tool

FAQ

Is it safe to merge PDF files online?
Yes — this tool processes your files entirely inside your browser using pdf-lib. Your files are never uploaded to any server, so there is no risk of data interception or third-party access.
How many PDFs can I merge at once?
There is no hard limit on the number of files. Browser memory is the practical constraint — typically 10–20 files of normal size work without issues.
Does merging work without an internet connection?
Yes. After the page loads once, the merge tool works fully offline thanks to a Service Worker that caches the tool locally.
Can I merge password-protected PDFs?
No. Password-protected PDFs cannot be opened by the browser's PDF engine. Please remove the password first using your operating system or Adobe Acrobat, then merge.
Will the merged PDF retain all original content?
Yes. Text, images, vector graphics, and page dimensions are preserved. Interactive form fields from each source PDF are also carried over.

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