---
title: "Merge PDF Files — Combine PDFs Privately | Compress Pro"
description: "Merge multiple PDFs into one document right in your browser — drag to reorder, optionally compress the result. Files never leave your device. Free."
canonical: https://compress-pro.com/merge-pdf
---

# Merge PDF files.

> Combine PDFs into one file locally — nothing is uploaded.

Combine any number of PDFs into a single document, assembled entirely in your browser. Drop the files, arrange them with the list arrows, and merge — pages are copied losslessly, so nothing is re-encoded unless you also tick “Compress after merging”. **No server ever touches your documents.**

**No uploads · No ads · Free & open source.**

## How it works

1. Drop files anywhere on the page, click to browse, or paste with Ctrl/⌘ + V.
2. Pick a quality or preset — or set an exact target size and let the tool find it.
3. Compress, compare before/after, and download — individually or as a ZIP.

## Merging without quality loss

The merge itself is lossless: pages are copied from each source PDF into the combined document exactly as they are — text, images, links and fonts are untouched, just reassembled. The output is only as large as its inputs combined, so if the result feels heavy, that weight was already in the sources.

## Merge and compress in one pass

Tick “Compress after merging” to hand the combined file straight to the same compression engine behind the [Compress PDF](https://compress-pro.com/compress-pdf) tool. This is the right order of operations — compressing one merged file beats compressing ten inputs separately, because images are downsampled once, consistently, and you check the size limit against the final document.

## Typical uses

| Task | How |
| --- | --- |
| Combine scanned pages | Drop the scans in shooting order — each becomes consecutive pages |
| Assemble a report | Cover, body and appendix PDFs in list order, compress at Medium |
| Bundle invoices | Merge a month of invoices, then compress to email size |

## Frequently asked questions

### How do I control the page order?

The merged PDF follows the list order — use the arrows on each row to rearrange files before merging. Pages inside each file keep their original order.

### Can I merge and compress in one step?

Yes — enable “Compress after merging” and the combined document is compressed right after assembly, with the preset you pick. Leave it off for a lossless merge.

### What about password-protected PDFs?

Encrypted files can’t be merged directly. Remove the password first with the Unlock tool — it runs locally too — then merge the unlocked copies.

### Are my documents uploaded?

No. The PDFs are opened and stitched together entirely in your browser — the merged document is assembled on your device, and nothing is ever transmitted anywhere. Want proof? Run one file through, switch your connection off, and run another — it still works.

## Related tools

- [Split PDF files](https://compress-pro.com/split-pdf)
- [Compress PDFs](https://compress-pro.com/compress-pdf)
- [Unlock PDF files](https://compress-pro.com/unlock-pdf)

---

Part of [Compress Pro](https://compress-pro.com/) — every tool page has a markdown twin at `<page url>.md`. Full tool index: [llms.txt](https://compress-pro.com/llms.txt)