Merge PDF

Combine several PDF files into one document in the order you choose. Processing happens locally in your browser.

Merge your PDF files

Add between 2 and 20 PDFs, arrange them, then merge and download the result.

Add PDF files

Drop PDFs here or choose them from your device.

About this tool

Merge PDF creates one PDF from multiple local files while preserving the displayed file order. It is a focused tool for combining complete documents, not editing individual pages.

What Merge PDF can do

The essential controls stay together in one clear workflow.

Add and inspect

Choose or drop several PDFs and see each file name, size, and page count.

Arrange the order

Move each PDF up or down with keyboard-accessible controls, or remove it before merging.

Merge and download

Combine every page in the displayed order and download one new PDF.

Get started

  1. Add at least two PDF files.
  2. Arrange the files in the order they should appear.
  3. Select Merge PDFs and wait for local processing to finish.
  4. Download the merged PDF.

Practical uses

  • Combine scanned pages or documents into one file.
  • Join reports, notes, or handouts in a chosen order.
  • Keep personal invoices or receipts together for organization.
  • Assemble chapters or PDF attachments into one document.

Data handling

Files are read and merged by code running in your browser. fourwww does not receive or process their contents on a server.

The selected files and merged result are kept only for the current page session. Clearing the tool or closing the page removes the tool’s references to them.

Technical scope and limitations

  • Add up to 20 PDFs. Each file may be up to 50 MiB, with a combined limit of 100 MiB.
  • Password-protected or encrypted PDFs are not supported.
  • Damaged or unsupported PDFs may not be readable.
  • This version merges complete PDFs only; it does not reorder, delete, rotate, or extract individual pages.
  • Large PDFs require browser memory beyond their file size, so the practical limit can vary by device and browser.

Frequently asked questions

Are my PDFs uploaded?

No. The files are processed locally in your browser and are not uploaded to fourwww.

Which order is used?

The merged PDF follows the order shown in the selected-files list. Every page from the first file comes before every page from the second, and so on.

Can I merge password-protected PDFs?

No. Unlock the PDF with an authorized tool before adding it here.

Does merging change the original files?

No. The original files remain unchanged; the tool creates a separate merged PDF for download.