Merge PDF

Combine multiple PDF files into one, reorder pages — fully client-side.

Loading tool…

Merge PDFCombine two or more PDFs into a single document, arranging the file order before merging. Processing is done with pdf-lib entirely in your browser — contracts, statements and other sensitive documents are never uploaded to a server.

What is Merge PDF?

Merge PDF is a free online PDF combiner that joins two or more PDF files into a single document right in your browser. Students, freelancers, and office workers use it to combine scanned pages, invoices, contracts, statements, and report chapters into one downloadable file. Because every PDF is processed locally with the pdf-lib library, you can reorder files before merging, preview the first page of each, and export a single merged.pdf without ever uploading sensitive documents. It is the tool to reach for whenever you need to combine, append, or stitch PDFs together quickly.

How to use Merge PDF

  1. Drag your PDF files onto the dropzone, or click it to browse and select multiple PDFs at once.
  2. Review the queued files; click any first-page thumbnail to zoom in and confirm you have the right document.
  3. Use the up and down arrow buttons on each row to set the order the files will be merged in, and use the X button to remove any file you do not want.
  4. Optionally tick 'Replace list when adding new files' if you want the next batch you add to start a fresh list instead of appending to the current one.
  5. Click 'Merge {count} files' (active once at least two PDFs are queued) to combine all pages into one file and download it as merged.pdf.
  6. Use the Clear button to empty the list and start over.

Examples

Combine scanned contract pages

Drop three separate scans named page1.pdf, page2.pdf and page3.pdf, arrange them in order with the up/down arrows, then click Merge to download a single merged.pdf containing all pages in sequence.

Append an appendix to a report

Add report.pdf first and appendix.pdf second; merging produces one PDF where the appendix pages follow the report pages, ready to send as a single attachment.

Reorder before merging

After adding statement-feb.pdf and statement-jan.pdf, move the January file above February with the up arrow (ChevronUp) so the merged document reads in chronological order.

Frequently asked questions

Are my PDF files uploaded to a server?
No. Everything runs 100% client-side in your browser using the pdf-lib library. Your files never leave your device and are never uploaded, which is why it is safe for contracts, statements, and other sensitive documents.
How many PDFs can I merge at once?
You can add as many PDF files as you like, but the Merge button only becomes active once at least two files are queued. All pages from every file are copied into one combined document.
Can I change the order of the files before merging?
Yes. Each file in the list has up and down arrow buttons so you can reorder it, plus an X button to remove it. Files are merged in the exact order shown in the list.
Why won't my file merge or why do I get an error?
The tool only accepts PDF files (.pdf); other file types are ignored when added. If you see 'Could not merge these PDFs,' one of the files may be corrupted or password-protected, which can prevent it from being combined.
What is the merged file named and what format is it?
The output is a standard PDF saved as merged.pdf. The merge keeps every page from each input file in the chosen order.

Related tools