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Merge PDF Files

Combine multiple PDF files into a single document. Drag to reorder, merge instantly. 100% browser-based. Zero uploads.

No Upload Required Multiple PDFs Drag to Reorder Preserves Quality

Drop your PDF files here

or click to browse – select multiple PDFs at once

PDF files only. Desktop: 256 MiB each / 768 MiB total. Phones or low-memory devices: 128 / 256 MiB.

How it works

Three simple steps – everything happens in your browser.

1

Upload PDF files

Select multiple PDFs within the displayed device budgets. Files are read one at a time during merging.

2

Arrange order

Drag files to reorder them. The order in the list is the order they appear in the final merged PDF.

3

Download merged PDF

Merge the selected pages and download one PDF. Review the output before sharing it.

Why choose ToolKnit for Merge PDF?

100% Private – No Server Uploads

Selected PDF bytes are processed locally with pdf-lib; they are not uploaded for merging. Loading site resources and visit analytics are separate network activity.

Merge on Your Device

No conversion upload is needed. Completion time depends on file complexity, total pages and your device's memory and speed.

Preserves Original Quality

Page artwork is copied without rasterizing it. Document-level features such as forms, bookmarks, signatures and some links may not survive page copying; check the result.

Drag & Drop Reorder

Simply drag files to rearrange the order. The page count for each file is shown so you know exactly what you are merging.

Pro Tips

  • ● You can add PDFs in batches – click "Add More" to append additional files after the initial selection.
  • ● Drag to reorder files before merging – the list order equals the page order in the final PDF.
  • ● Check interactive forms, bookmarks, links and digital signatures separately; page copying is not a guarantee that these document features remain valid.
  • ● For large merges, reduce the batch or close unused tabs if memory becomes limited. Browser and device capacity vary.
Learn More

New to merging PDFs?

Read our step-by-step guide covering tips, troubleshooting, and best practices for combining PDFs.

Read Guide
FAQ

Frequently Asked Questions

Is the Merge PDF tool free?

Yes. There is no ToolKnit subscription or watermark. The site's shared browser usage counter applies across tools; processing runs locally.

Are my PDF files uploaded to a server?

No. All merging happens locally in your browser using pdf-lib. Your files never leave your device.

How many PDF files can I merge at once?

There is no fixed file-count cap. Desktop input budgets are 256 MiB per file and 768 MiB in total; phones or low-memory devices use 128 MiB and 256 MiB. Each source can contain up to 10,000 pages. Content complexity and output memory can reach a limit earlier.

Can I change the order of the PDFs before merging?

Yes. Drag the files in the list to reorder them. The order shown is the exact order of pages in your final merged PDF.

Will merging reduce the quality of my PDFs?

The tool copies page content without re-rendering it as images. That does not guarantee preservation of forms, bookmarks, signatures or every link; inspect the merged file.

Do I need to install any software?

No. Merge PDF is a 100% browser-based tool – no app, no plugin, no signup. Just open the page, add your PDFs, and merge.