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PDF Merger

Combine multiple PDF files into a single document - 100% client-side

Combine PDFsPage OrderingBrowser-basedNo Upload Needed

Upload PDF Files

Select multiple PDF files to merge into one document

Drop files here or

Maximum file size: 50MB • Files: 0 / 20

Accepted file types: .pdf

Download Result

Download your merged PDF document

No files available for download. merged PDF file to generate your result.

About this tool

Combine multiple PDF files into a single, unified document with complete control over page order and structure. Our browser-based PDF merger processes everything locally — no file uploads, no cloud servers, and no privacy risk.

About

How PDF Merging Works and Why Page Order Matters

Merging PDFs is more than concatenating byte streams — it involves resolving conflicting object references, merging cross-reference tables, and combining page trees from separate document roots. Each PDF contains its own object hierarchy: pages, fonts, images, and annotations all referenced by unique object IDs. A proper merger renumbers these objects to avoid collisions and rebuilds a unified xref table so PDF readers can navigate the combined document reliably.

Page ordering is critical in professional workflows. Whether you're assembling a report with appendices, combining scanned contracts, or archiving correspondence, the final page sequence defines how recipients experience the document. Our tool lets you drag and rearrange files before merging, giving you precise control without multiple re-exports.

All processing happens inside your browser using the pdf-lib JavaScript library — your files never leave your device. This makes the tool safe for sensitive documents like legal contracts, financial statements, and medical records while delivering the same output quality as desktop PDF applications.

Common Use Cases
1

Combine report chapters into one PDF

Export each section separately from different authors, then merge them into a single branded document for distribution.

2

Assemble multi-page scanned contracts

Scanners often produce one PDF per page — merge them into a complete contract package without re-scanning.

3

Bundle invoices for accounting

Consolidate monthly invoices into a single file for easier attachment to expense reports or audit submissions.

4

Create portfolios from individual projects

Merge project PDFs, case studies, and résumés into one portfolio document for job applications or client pitches.

How to Use
  1. 1

    Upload your PDF files

    Click the upload area or drag multiple PDF files onto it. You can select as many files as needed — there's no hard limit on file count, though very large batches may take longer to process.

  2. 2

    Arrange the page order

    Drag the file thumbnails to set the sequence in which pages will appear in the merged document. The order you set here is exactly what the output will reflect.

  3. 3

    Merge and download

    Click Merge PDF to combine all files in your browser. Once processing completes, download the resulting single PDF file to your device.

Features
  • Drag-and-drop page reordering

    Visually rearrange files before merging so your final document has exactly the page sequence you need — no guesswork.

  • Unlimited file count

    Merge two files or twenty — the tool handles batches of any size, making it practical for large document assembly workflows.

  • 100% client-side processing

    Files are processed entirely in your browser using pdf-lib. Nothing is uploaded to any server, protecting sensitive document contents.

  • Preserves fonts and images

    The merger maintains embedded fonts, vector graphics, and high-resolution images from source PDFs without recompressing or downgrading quality.

Frequently Asked Questions

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