The PDF Alternate Merge tool combines two PDF files by interleaving their pages into a new PDF, such as A1, B1, A2, B2. Processing runs locally in your browser, and files are not uploaded to a server.

Use Cases

• Restore a duplex-scanned document from separate front-side and back-side PDFs.
• Sort contracts, invoices, receipts, and scanned archive files by page order.
• Combine two similarly sized PDFs in a fixed alternating sequence.

How to Use

1. Select or drag PDF A and PDF B.
2. Choose whether A or B should start the interleaving order.
3. Use reverse order for PDF B if the back-side scan runs from the last page to the first page.
4. Decide whether to append remaining pages from the longer file.
5. Check the page preview to confirm the current interleaved order.
6. Generate the interleaved PDF and download the result.

Options

• A first: outputs A1, B1, A2, B2.
• B first: outputs B1, A1, B2, A2.
• Reverse B: uses PDF B from the last page first, useful for some duplex scan workflows.
• Append remaining pages: keeps extra pages when the two PDFs have different page counts.
• Page preview: shows pages in the current output order and indicates whether each page comes from PDF A or PDF B.

Notes

• Encrypted, damaged, or unsupported PDF files may not be processed.
• If the final page order is wrong, first try changing the PDF B page order.
• Large PDFs require more browser memory and processing time.