PDF Merger

How to Use

1. Drop or select your PDFs. Drag and drop multiple PDF files onto the upload area, or click to browse and select them. The tool accepts as many files as your device memory can handle.
2. Arrange the order. Use the up/down arrows next to each file to reorder. The final PDF follows this order from top to bottom.
3. Merge and download. Click Merge PDFs to combine all files into a single document. Save it directly to your device — nothing is sent to a server.

Why Use This Tool

• Your PDFs never leave your browser. The pdf-lib library runs entirely client-side using JavaScript and the File API. You can verify zero network activity in DevTools.
• No file size limits, no daily quotas, no premium tier behind a paywall. Merge a hundred contracts or a thousand-page report in one go.
• Preserves original quality, fonts, vector graphics, images, and annotations exactly as the source files contained them. No re-encoding, no quality loss.
• No account or sign-up. Open the page, drop files, get the merged PDF in seconds.
• Works offline once the page has loaded — useful when handling sensitive documents on a network you do not trust.

Frequently Asked Questions

Do my PDFs get uploaded to a server?

No. All merging happens in your browser using the pdf-lib library. Your files never travel over the network. Open DevTools → Network and watch — when you click Merge, zero requests are made. The browser reads the files locally, performs the merge in memory, and prepares a download blob — all within your device.

Is there a limit on how many files I can merge?

No fixed limit. The merger handles as many PDFs as your device memory allows. Most modern laptops and phones comfortably merge 50 to 100 files. For unusually large collections (500+ files or multi-gigabyte totals), you may notice the browser tab slowing down — that is normal local memory pressure, not a tool limit.

Will the merged PDF preserve fonts and images?

Yes. Pages are copied from the source PDFs as-is, including embedded fonts, raster images, vector graphics, form fields, and annotations. The merger does not re-render or re-compress — it appends pages while preserving their original byte content. The result looks identical to the source.

Can I reorder files before merging?

Yes. After dropping multiple PDFs, each appears in a list with up/down arrows. Click the arrows to move files. The final document follows the order shown top-to-bottom. You can also remove a file from the list before merging.

Does this work on mobile devices?

Yes. The interface is fully responsive and works on iOS Safari, Chrome on Android, and other modern mobile browsers. Touch interactions are supported for the reordering controls. Performance depends on the device — older phones may struggle with very large PDFs (over 100 MB combined).

Can I merge password-protected PDFs?

Password-protected PDFs must be unlocked before merging. If you know the password, use our PDF Password Remover tool first to produce an unlocked version, then merge the unlocked files. We never receive or store your passwords — everything runs in the browser.