WrenPDF

Merge PDF

Drag to reorder multiple PDF files and merge them into a single document.

What it does

Job applications, visa paperwork and month-end accounting all end the same way: someone asks for "everything in one PDF". This tool joins your files in the order you choose. Pages are copied, not redrawn, so text stays selectable, links keep working and image quality is untouched.

The merge runs in a separate thread in your browser (a Web Worker). Nothing is uploaded, so you can combine payslips, medical letters or signed contracts without handing them to a third party.

How to use it

  1. Drop your PDF files into the box (you can select more than one).
  2. Drag the list into the order you want.
  3. Press "Merge and download"; the job runs in the worker and the interface never freezes.

When is it useful?

  • Sending a CV, diploma and certificates as a single attachment
  • Passing a month of invoices or bank statements to your accountant
  • Turning a stack of single-page scans into one document
  • Archiving lecture notes or slides at the end of a term

Tips

  • Prefix file names with numbers ("01-cover", "02-letter") and the list arrives in the right order.
  • If the merged file is too big to email, send it straight to Compress PDF with one click.
  • To reorder or delete individual pages after merging, open the result in Page Organizer.

Frequently asked questions

How do I change the page order?
Drag the rows to reorder them. On touch screens, use the up and down arrows on each row.
Can I merge password-protected PDFs?
No. Encrypted files are flagged in the list; remove the password first and add them again.
Does the page freeze while merging?
No. The merge runs in a separate Web Worker, so you can keep editing the list.
What happens when the PDFs have different page sizes?
Each page keeps its own size. A4 and Letter pages can sit in the same document, and your printer scales each page as it prints.
Are bookmarks and form fields kept?
Page content, text and images are kept. Bookmarks and fillable form fields from the source files may not carry over, so fill in and save any form first.

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