Alternate Merge interleaves pages from two PDFs in an alternating pattern — page 1 from file A, page 1 from file B, page 2 from file A, page 2 from file B, and so on. This is the go-to tool for reassembling double-sided scans when you scanned the front and back pages into separate files. Alternate Merge sits in FilePilot's pdf tools collection, so it is easy to move between this task and nearby tools such as Free Online PDF Tools, Free Online Image Tools, Merge PDFs. It is useful when you need to reassemble double-sided scans from a single-sided scanner; interleave question sheets and answer sheets; combine two parallel document versions page-by-page; merge translated and original-language pages side by side. The workflow is straightforward: upload the first pdf (e.g., front sides of scanned pages); upload the second pdf (e.g., back sides); click "merge" to interleave the pages and download the result. The work happens locally in your browser using client-side processing, which keeps your files on your device and gives crawlers a clear plain-text description of what this page does before the interactive app loads.
It interleaves pages from multiple PDFs: page 1 of doc 1, page 1 of doc 2, page 2 of doc 1, etc. — perfect for merging duplex scans.
No. All processing is done in your browser. Your files never leave your device.