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KX Toolkit

PDF Merger

Combine multiple PDFs into a single file. 100% browser - your files never upload.

PDF Tools

Select 2 or more PDF files. Drag the rows to reorder before merging.

    Combine multiple PDFs into a single file. 100% browser - your files never upload.

    This free PDF Merger from KX Toolkit is part of our all-in-one online toolkit. It runs entirely in your browser, so your data never leaves your device for client-side operations. 100% free, forever - no paywall, no credit card, no trial.

    How to use the PDF Merger

    1. Drop your PDF(s) into the upload area.
    2. Pick options - pages to split, compression level, output format.
    3. Click "Process" and wait a few seconds.
    4. Download the result. Files are deleted from the server immediately after.

    What you can do with the PDF Merger

    • Combine multiple invoices into one PDF for accounting.
    • Shrink a 50MB report to email-friendly size.
    • Extract specific pages from a long document.
    • Convert PDFs into editable Word documents.

    Why use KX Toolkit's PDF Merger

    • Browser-based: Works on Windows, macOS, Linux, iOS and Android - no install, no extension.
    • Privacy-first: Client-side tools never upload your data; server-side tools delete files right after processing.
    • Mobile-friendly: Full feature parity on phones and tablets - not a stripped-down view.
    • Fast: Optimised for instant feedback. No artificial waiting screens, no email-gated downloads.
    • One hub for everything: 300+ tools across SEO, text, image, PDF, code, color, calculators and more - skip switching between sites.

    Tips for the best results

    For sensitive documents, prefer client-side tools where indicated - your file never reaches the server.

    Related PDF Tools

    If you find this tool useful, explore the full PDF Tools collection or browse our complete tool directory. KX Toolkit is built for marketers, developers, designers, students and anyone who needs a quick utility without signing up for yet another SaaS.

    How do I combine multiple PDF files into one document?
    Drag your PDF files into the merger or pick them with the file selector. Reorder them by dragging the thumbnails so the final document follows the sequence you want. When you are happy with the order, click merge and a single combined PDF is built right inside your browser. The download starts as soon as it is ready. There is no limit on how many separate files you can add, although very large batches may take a few seconds to assemble.
    Are my PDFs uploaded to a server when I merge them?
    No. The merger uses the PDF.js and pdf-lib libraries that run entirely inside your browser, so the files never leave your device. This makes it safe to combine confidential contracts, medical records or financial statements without worrying about a server seeing them. Because the work happens locally there is no upload wait either, and you can use the tool offline once the page has loaded. Your privacy is fully protected by design.
    Is there a maximum file size or page count for merging?
    There is no fixed cap, but practical limits depend on your device's memory. Most modern laptops handle 200 to 300 pages or a combined size of a few hundred megabytes without trouble. If you try to merge very large scanned PDFs the browser tab may slow down or run out of memory. In that case split the job into smaller batches, or close other heavy tabs first. The merged file is built in memory before being offered for download.
    Will merging preserve bookmarks, links and form fields?
    Page content, images and most internal links are preserved exactly as they were in the original files. Bookmarks and form fields can sometimes be dropped because pdf-lib rebuilds the document structure during the merge. If you rely heavily on bookmarks, add them again in a dedicated PDF editor after merging. Annotations such as highlights and comments usually carry over fine. The visual appearance of every page stays identical to the source documents.
    Why does my merged PDF say it is encrypted or refuses to open?
    The most common cause is one of the source files being password protected. The merger cannot read encrypted PDFs without the password, so remove the protection first using the password remover tool and then try again. Another cause is a corrupted source file, which you can detect by opening each PDF separately. Once all inputs open cleanly, the merge produces a standard unencrypted PDF that any reader can open.
    Can I merge a mix of text PDFs and scanned image PDFs?
    Yes. The merger does not care whether each page contains real text or just a scanned image, it simply stacks the pages together. The output keeps each page in its original form, so text pages stay searchable and scanned pages remain images. If you want the scanned pages to become searchable too, run them through an OCR tool before merging. The combined file size is roughly the sum of the inputs, sometimes a little smaller.

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