Interleave Front and Back PDF Scans

Front-page PDF

Back-page PDF

On by default for a turned-over stack. Turn off when the backs are already in reading order.

Combine two PDFs from a single-sided scanner into one document with alternating front and back pages. Reverse the back-page order when the second scan runs backwards.

Review the page arrangement before downloading. Pages are copied without reducing their image resolution, and different page counts keep every extra page at the end.

Frequently Asked Questions

How should I scan the two sides?

Scan all fronts into one PDF and all backs into another. Back-page reversal is on by default because turning a stack over often reverses its order. Turn it off if the back PDF already starts with the first sheet’s back, and check the arrangement preview.

What happens if the page counts differ?

Available front and back pages are paired first. Every remaining page is appended in its selected order, with a notice showing the unequal counts. No pages are discarded and no blank pages are inserted automatically.

Does merging change the scanned image quality?

The original page content, rotation and crop area are copied without rendering pages into new images. The result is a new PDF; document bookmarks, interactive form behavior and digital signature validity are not preserved. Keep the originals if you need those features.

Are my PDFs uploaded?

No. Reading, previews and merging happen in your browser. Password-protected PDFs need an unlocked copy first. Large documents depend on your device’s available resources; cancelling keeps your selected files so you can retry.

Related tools: Merge PDF · PDF Page Organizer

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