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Centilio › Free tools › Merge PDF

Merge PDF files, free and private

Merge PDF files in your browser, free. Files never leave your device. From the makers of Centilio Sign.

Standalone utility · no account connection · inputs stay on this device. JavaScript is required for calculations and file processing.

    Up to 30 files, 50 MB combined and 500 pages. Your files stay on this device. Keep the originals; signatures and interactive document features may not survive a page merge.

    How it works

    Pick two or more PDFs. They are combined in the order shown, with every page kept at its original size. Large files take a few seconds; nothing is uploaded.

    Choose at least two PDF files.

    About this tool

    Combine PDF pages in your browser, preserving their original size and orientation. Nothing is uploaded. This is a page merge, not a guarantee that digital signatures, interactive forms, bookmarks or all document metadata will survive; keep your originals.

    Once merged, if the document needs signatures, Sign will place the fields for you and collect them.

    Questions

    Are my PDFs uploaded?

    No. The merge runs entirely in your browser using the pdf-lib library. Your files stay on your device.

    Is there a size or file limit?

    This tool accepts 2–30 PDF files, up to 50 MB combined. Your device’s available memory may impose a lower limit. Encrypted or damaged PDFs are rejected.

    Can I reorder or remove pages?

    Files are merged in the displayed order. Use Move up, Move down or Remove before merging. Splitting individual pages is not included.