Sooner or later every PDF user needs to glue files together: a cover letter in front of a CV, a contract followed by its appendices, several scanned chapters that belong in one book, or a month of invoices combined for the accountant. The Merge PDF tool concatenates any number of PDFs into a single document while preserving every page exactly as it was — same fonts, same images, same layout — and it does so without sending your files anywhere.
How to use the Merge PDF tool
- Add two or more PDF files by dragging them in or browsing.
- Drag the file names to set the order they will appear in.
- Remove anything you added by mistake with the × button.
- Click Merge PDFs and download the combined document.
Why merging beats sending separate files
A single merged PDF is simply easier for everyone downstream. The recipient opens one file instead of juggling five, the pages stay in the sequence you intended, and the whole bundle prints in one job. Offices, law firms and universities almost always prefer one consolidated document because it cannot be split up, reordered or partially lost in an inbox. Merging is also the first step before adding page numbers or a watermark to a complete set.
Tips for a clean merge
- Check the order twice; the document follows your list from top to bottom.
- Merge first, then number the pages so the count runs continuously across the whole file.
- Watch the total size if the originals are image-heavy — combining ten scanned PDFs creates one large file.
- Keep originals until you have confirmed the merged result looks right.
The tool is powered by the pdf-lib engine, which copies each page intact rather than re-rendering it, so quality never degrades. Everything runs in your browser, meaning confidential contracts and personal records are combined entirely on your own machine.
Quick reference
| Property | Detail |
|---|---|
| Input | Two or more PDF files |
| Output | Single merged PDF |
| Order | Drag to reorder |
| Fidelity | Pages copied exactly |
| Upload | None — fully local |