PDF Merger
Combine multiple PDF files into one — runs entirely in your browser, no uploads.
Drag & drop PDF files here
or click to browse — multiple files allowed
What is PDF Merger?
A PDF merger combines two or more separate PDF files into a single document. This is one of the most common document tasks in offices and schools: combining chapters of a report, merging separately scanned pages into one file, assembling a portfolio, combining multiple forms into a submission package, or joining supporting documents into a single attachment.
PDF (Portable Document Format) is the universally accepted format for sharing documents — it preserves layout, fonts, and images across all devices and operating systems. When you have multiple PDFs that need to be shared together, merging them into one file simplifies distribution, reduces email attachment count, and ensures recipients receive everything in the correct order.
Altairys's PDF Merger lets you upload multiple PDF files, reorder them by dragging, and merge them into a single file. You can also choose specific page ranges from each file to include — useful when you only need certain pages from a large document. The merging is performed entirely in your browser using pdf-lib, a zero-dependency JavaScript library. This means your documents — which may contain sensitive financial, legal, or personal information — never leave your device.
How to Use PDF Merger
- Upload your PDFs
Drag and drop two or more PDF files onto the upload area.
- Reorder the files
Drag files to rearrange their order — the first file becomes the first pages.
- Set page ranges (optional)
Optionally specify which pages to include from each PDF.
- Merge and download
Click Merge and download your combined single PDF file.
Key Benefits
Arrange PDFs in any order by dragging before merging.
Include only specific pages from each PDF, not the entire document.
PDF contents never leave your browser — safe for confidential documents.
Merge as many PDFs as your device memory allows — no artificial restrictions.
Supported Formats
Frequently Asked Questions
There is no hard limit. You can merge as many files as your device's memory supports — tens of files and hundreds of pages are typically handled without issues.
Basic content (text, images, layout) is fully preserved. Complex features like bookmarks and internal hyperlinks may not survive merging depending on the source PDFs.
Yes. The merged document preserves each page at its original size. Pages from A4 and Letter documents can coexist in the same merged file.
Yes — use the page range selector to specify which pages from each PDF to include. This lets you cherry-pick pages from multiple documents.
Password-protected PDFs cannot be merged without removing the password first. Use Altairys's PDF Password Remover tool, then merge.