buncha.tools
buncha/pdf/pdfmerge

PDF Merge

Read the guide
How to Merge PDFs in Your Browser (No Upload, No Account)

Pairs well with

PDF Sign
Sign PDF documents online. Draw your signature and
PDF Watermark
Add a text or image watermark to every page of a P
Image to PDF
Combine multiple images into a single PDF — drag t
PDF Form Fill
Fill out PDF forms online. Type into fields, check

About PDF Merge

Merge multiple PDFs into one — drag to reorder, drop to combine. Runs entirely in your browser using pdf-lib; your files never upload anywhere.

How to use it

  1. Drop your PDFs onto the upload zone.
  2. Drag the thumbnails to reorder.
  3. Click Merge to combine.
  4. Download the result.

Most online PDF mergers upload your files to a server, process them there, and email or hand back a link. That’s a privacy hazard if the PDFs contain anything sensitive (contracts, medical records, tax docs). This one runs in your browser via pdf-lib — the file never leaves your device.

Output preserves the original page sizes, fonts, and bookmarks. PDF/A and form fields are kept on a best-effort basis; encryption is preserved as long as you can open all the input files.

Common questions

Is there a file size limit?
Limited only by your browser's memory. Phones tend to choke around 50MB; laptops handle 500MB+ fine.
Are my PDFs uploaded?
No. Everything happens in your browser. Pull the network tab and you'll see no requests during the merge.

Like every tool on Buncha, this one runs entirely in your browser. There's no upload, no log, no record of what you've pasted or generated. Close the tab and the data is gone.

↳ Have feedback or found a bug? hello@buncha.tools
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Built browser-first. Run by one developer.
Every tool runs on your device. No tracking pixels, no sign-up to start. The numbers below are pulled live from the registry.
240
Free tools
Across 14 categories
7
Visual editors
PDF · image · video · audio
32
Curated kits
By profession + lifestyle
17
AI tools
Powered by Claude API
Files never uploadNo tracking pixelsNo sign-up neededWorks in any modern browser
The handful of AI tools (paraphrase, summarise, blog, captions, etc.) send your prompt text to Anthropic's Claude API to do the work. Files, images, PDFs and video never leave your device. Pick the tools that fit your privacy comfort.