Merge PDF Files

Combine multiple PDF files into one document. Drag to reorder, then merge. 100% client-side — your files never leave your browser.

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Drop PDF files here
or click to browse — accepts .pdf only
Your PDFs never leave your device. All merging happens in your browser using pdf-lib. Nothing is uploaded to any server.

How to Merge PDFs

1

Add Your Files

Drag and drop PDF files onto the drop zone (or anywhere on the page), or click Browse Files to select them from your device.

2

Reorder if Needed

Drag the ⠇ handle on each file to rearrange, or use the ↑ ↓ buttons for mobile-friendly reordering.

3

Name, Merge & Download

Set your preferred output filename, click Merge PDFs, then Download to save your combined document.

Frequently Asked Questions

Are my PDF files uploaded to a server?

No. All processing happens entirely in your browser using the pdf-lib JavaScript library. Your files are read into memory locally and never transmitted over the network. This makes the tool safe for confidential documents.

Is there a file size limit?

There is no hard limit imposed by the tool. Processing happens in your browser's memory, so very large files (500 MB+) may slow down depending on your device's RAM. Most typical documents (contracts, reports, scans) merge instantly.

Can I reorder the PDFs before merging?

Yes. Each file in the list has a drag handle on the left. Click and drag it to rearrange files in your preferred order. On mobile or if drag is inconvenient, use the ↑ and ↓ arrow buttons next to each file. The final merged PDF pages will follow the sequence shown in the list, top to bottom.

What happens with password-protected PDFs?

Encrypted or password-protected PDFs cannot be read by the browser. The tool will display an error for any file it cannot open. You would need to unlock the PDF first using its password in another tool, then add it here.

Does merging reduce PDF quality?

No. The tool copies pages directly from each source PDF into the merged document without re-encoding or compressing. Images, fonts, vector graphics, and form fields retain their original quality.

How many files can I merge at once?

There is no hard limit on the number of files. You can add as many PDFs as your browser's memory allows. In practice, merging 20–50 typical documents works smoothly. Very large batches (100+ files or several hundred MB total) may slow down on older devices.

Can I merge PDFs from my phone?

Yes. The tool works on any modern mobile browser (Chrome for Android, Safari on iOS). Use the Browse Files button to open your device's file picker. Drag-to-reorder uses drag handles on desktop; on mobile, use the ↑ ↓ buttons next to each file to change the order.

What browsers are supported?

Any browser that supports the File API and Blob/URL.createObjectURL: Chrome 90+, Firefox 88+, Edge 90+, Safari 14+, and their mobile equivalents. Internet Explorer is not supported.