Merge PDF
Combine multiple PDFs into one file, free, in your browser.
.pdf · up to 100 MB
Why use this tool
Multiple PDFs, one file
Any source
Combine PDFs from different departments, apps, or authors into a single document.
100% private
Your documents are processed in your browser. Never uploaded to any server.
Exact order
Drag to reorder files before merging. The result respects your order.
Immediate result
Merging completes in seconds, no waiting or queues.
How it works
Three steps, no hassle
Upload your PDF files
Drag or select all the PDFs you want to merge. You can add files from different folders or departments.
Arrange the documents
Drag files to set the correct order before combining them.
Download the merged PDF
Click Merge and download your new PDF with all pages in a single file.
FAQ
Got questions?
Files are merged exactly in the order shown in the list. You can drag each file to reorder them before merging.
You can merge as many files as your browser can handle. For most use cases (2-20 normal-sized files) there is no issue. For very large combinations, processing time may increase.
Bookmarks from original documents are included in the merged PDF when the processing library supports them. For documents with complex indexes, check the final result.
Each page keeps its original size. One PDF can have A4 pages and another Letter size, and the merged document will preserve each page size exactly as it was.
Generally the size is similar to the sum of the original files. No additional compression is applied during merging. If you need to reduce the size, use the Compress PDF tool afterward.
No. Password-protected PDFs cannot be processed without first removing the protection. You need a PDF without editing restrictions to merge it with others.
Merge PDF: how to combine documents from different sources
Merging multiple PDFs into one is a common need in work environments: reports from different departments, contracts with annexes, presentations with appendices. The PDF format was designed to be a final, immovable document, which means combining several files requires a dedicated tool.
The technical process of merging PDFs involves reading the internal structure of each file (pages, resources, metadata) and constructing a new document containing them all in sequence. Libraries like pdf-lib allow this to be done directly in the browser, without requiring servers.
Convertir.ai merges your PDFs entirely in your browser. Your documents — which may contain confidential information, contracts, or internal data — never leave your device. Unlike cloud services like Smallpdf or ILovePDF, there are no daily limits and no account required.