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Merge PDF

Local

Combine multiple PDF files into one document

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Merge PDF
Local
Tool Details
Input formatsPDF
Output formatPDF
Max file size100 MB
Max files100
ProcessingLocal

Privacy First

Your files are processed entirely in your browser. Nothing is uploaded to any server.

How do I merge PDF files into one?

Add two or more PDFs, use the arrow controls to put them in the order you want, then merge and download the combined file. Every page of each document is copied into a single new PDF in list order, so a cover letter, a CV, and a portfolio become one attachment. The documents are opened and joined by this browser tab, never uploaded.

About the Merge PDF

Merge multiple PDF files into a single document in your browser. Select up to 100 PDFs in the order you want them combined, then download one file without uploading documents to a server.

  • Combine forms, invoices, scans, reports, or signed documents into one PDF.
  • Merge up to 100 PDF files while keeping the file order you selected.
  • Prepare a single upload-ready document for portals that only accept one PDF.

How to use the Merge PDF tool

  1. 1

    Upload PDF files

    Select PDF files from your device or drag files into the upload area.

  2. 2

    Review files

    Review the selected files and continue when they are ready.

  3. 3

    Merge PDFs

    Run the Merge PDF tool to create the PDF output.

  4. 4

    Download the result

    Download the finished file. The original file stays on your device and is not uploaded.

Does merging PDFs reduce quality or re-compress pages?

No. Merging copies each page object into a new document rather than rasterising or re-encoding it, so text stays selectable, vector diagrams stay sharp at any zoom, and embedded images keep their original compression. The merged file is roughly the sum of its parts in size. This is the difference between a page-level merge and the "print to PDF" route, which flattens everything into images and quietly destroys the text layer.

How do you control the order pages appear in?

The order of the file list is the order of the output — the first file supplies the first pages, and so on. Arrange the list before merging rather than after, because reordering the finished PDF means a second pass through the rearrange tool. If a single document needs to be inserted into the middle of another, split the larger file first, then merge the three parts in sequence.

What happens to bookmarks, forms, and annotations?

Page content, including text and images, carries over reliably. Document-level features are less predictable: outlines and form field structures live at the document root rather than on individual pages, so they may not survive the copy. If the source PDFs contain fillable forms you need to keep working, merge them last, or flatten the forms first so the values become permanent page content.

Are my files uploaded when merging PDF files?

No. The merge happens entirely in this tab: each file is read from disk into memory, the pages are copied into a new document, and the result is handed back as a download. That matters more here than for most tools, because merging is what people do to assemble complete application packs, medical records, and signed contracts — collections that are far more sensitive than any single page in them.

How to do this offline, on the command line

qpdf concatenates without re-encoding, so nothing degrades.

qpdf

macOS: brew install qpdf · Debian/Ubuntu: apt install qpdf

qpdf --empty --pages a.pdf b.pdf c.pdf -- merged.pdf

Add a page range after any input, e.g. b.pdf 2-5, to take only part of it.

Ghostscript

macOS: brew install ghostscript · Debian/Ubuntu: apt install ghostscript

gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -sOutputFile=merged.pdf a.pdf b.pdf

Rewrites and normalises the output, which can shrink it but also drops some interactive features.

Frequently Asked Questions

How do I merge PDF files in order?
Add the PDFs in the sequence you want before running the merge tool. The combined PDF follows that selected file order.
How many PDFs can I combine?
You can merge up to 100 PDF files, with each file up to 100 MB.
Are merged PDFs uploaded to PDFBase?
No. PDFBase merges the files locally in your browser, so the documents stay on your device.

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