Interleave Two PDFs
Merge the two halves of a duplex scan into one correctly ordered PDF. Upload the odd/front pages as PDF A and the even/back pages as PDF B - they interleave page by page into a single document, all processed privately in your browser.
Privacy: Both PDFs are processed only in your browser — nothing is uploaded, no server sees them.
How to use
- Select the PDF that holds the front / odd pages (1, 3, 5 ...) as PDF A.
- Select the PDF that holds the back / even pages (2, 4, 6 ...) as PDF B.
- Keep reverse B checked if your scanner scanned the back side in reverse order (this is the usual duplex behaviour).
- Click Interleave & Download. Pages are merged as A1, B1, A2, B2 ... and the result downloads automatically.
Tips
- If your scanner saved the back side in reverse order, keep reverse B checked - most duplex scanners do this.
- Verify PDF A really holds the odd pages (1, 3, 5) before merging; mixing them up garbles the order.
- For long documents, merge a few pages first as a test before committing the whole file.
- Everything runs in your browser - safe for sensitive scanned documents.
Frequently Asked Questions (FAQ)
What does interleave PDF mean?
It merges two PDFs page by page: PDF A (odd and front pages) and PDF B (even and back pages) are joined in alternate order into one PDF.
When would I use this?
It is the most common task after duplex scanning, when each side of a document was scanned into a separate file.
Are my files uploaded?
No, your files stay in your browser; nothing is uploaded.
What does the reverse-order option do?
Duplex scanners usually scan the back side in reverse order, so keep it checked to merge pages correctly as A1, B1, A2, B2 and so on.