Merge PDF Files
Drop your PDFs below, reorder if needed, and combine them into one document.
Drop your PDF files here
or click to browse — PDF files only
How PDF merging works
OnlyFiles uses pdf-lib to combine your PDF files entirely in your browser. Each PDF is read as binary data, and the pages are copied into a new combined document in the order you specify. All page content — text, images, annotations, bookmarks — is preserved exactly. The merged PDF is a standard, valid document that works in every PDF reader.
Your files never leave your device
Unlike most online PDF merge tools that upload your files to a server, OnlyFiles processes everything locally in your browser tab. This makes it safe for confidential contracts, financial statements, medical documents, or anything else you wouldn't want on someone else's server. You can verify by disconnecting from the internet after the page loads — the merge still works.
When to use this
- Combine multiple scanned pages into one document for submission
- Join a cover letter and resume into a single PDF for job applications
- Merge invoices, receipts, or contracts into one file for record-keeping
Frequently asked questions
How do I merge PDF files for free?
Go to onlyfiles.org/merge-pdf, drop your PDF files, reorder them if needed, and click Merge. Your combined PDF downloads instantly. No signup, no watermarks.
Is it safe to merge PDFs online?
OnlyFiles merges PDFs entirely in your browser using pdf-lib. Your files are never uploaded to any server — they stay on your device the entire time.
How many PDFs can I merge at once?
There is no hard limit on the number of files. You can merge as many PDFs as your browser can handle. For very large files, the merge may take a few seconds longer.