Free PDF Merger - Combine Multiple PDFs

Merge multiple PDFs in your browser with pdf-lib. Private, unlimited, and no upload of your document bytes to WebTooly.

About PDF Merger

`pdf-lib`: `PDFDocument.create()`, then for each file `PDFDocument.load(arrayBuffer)`, `copyPages(source, source.getPageIndices())`, `addPage` each copied page, then `save()` to a `Blob`.

How it works (technical)

Page order follows the file list UI; remove/re-add to reorder.

Merging copies page content into a new PDF—no server round-trip.

Total RAM limits apply for very large jobs; password-protected PDFs fail until unlocked.

When to use it

  • One attachment

    Combine scanner exports or chapters into a single upload.

  • Documentation packs

    Append appendices or signed pages to a base PDF.

  • Offline-friendly

    Merge when you do not want files on a third-party server.

How to Use PDF Merger

  1. 1Upload multiple PDF files by dropping them or clicking to browse.
  2. 2Arrange the files in your desired order by removing and re-adding.
  3. 3Click "Merge PDFs" to combine all files into one document.
  4. 4Download the merged PDF file to your device.

Key Features

  • `PDFDocument` merge via `copyPages`
  • All pages per file, in list order
  • Standard PDFs `pdf-lib` can load
  • Single downloadable blob

Benefits

  • One output file
  • Vector content copied, not rasterized
  • Client-side processing

Frequently Asked Questions

How many PDF files can I merge?

There is no limit to the number of PDF files you can merge. However, very large files may take longer to process in your browser.

Will the merged PDF maintain quality?

Yes, our merger preserves the original quality of all text, images, and formatting from your source PDF files.

Is my data secure when merging PDFs?

Absolutely. All PDF processing happens locally in your browser. Your files are never uploaded to our servers.

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