Are my PDF files uploaded to a server?

No. All processing happens locally in your browser using PDF.js. Your files are never sent to any server.

Can I reorder the PDFs before merging?

Yes. Drag and drop to set the order of the input files before merging.

Is there a file size limit?

There is no imposed limit. Performance depends on your device and browser memory, so very large files may be slower.

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Combining multiple PDF files into one is one of the most common document tasks, and most dedicated tools either require a subscription or upload your files to a cloud server. devtoolkit.sh's PDF Merger does the entire operation in your browser — your files never leave your device. Drag any number of PDFs into the tool, reorder them as needed, and download the merged result in seconds. This is ideal for assembling multi-part reports, combining invoice scans for expense submission, packaging multiple attachments into a single deliverable, or merging split document chapters. No signup, no upload, no file size limits beyond your browser's available memory.

Select PDF files to merge

FAQ

Are my PDF files uploaded to a server?: No. All processing happens locally in your browser using PDF.js. Your files are never sent to any server.
Can I reorder the PDFs before merging?: Yes. Drag and drop to set the order of the input files before merging.
Is there a file size limit?: There is no imposed limit. Performance depends on your device and browser memory, so very large files may be slower.