Alternate & Mix PDF
Local Processing (Offline Capable)Interleave two PDFs page by page (merge front/back scans), or reverse page order for a single PDF. Runs locally in your browser — your file is never uploaded. For sequential appending, use Merge PDF.
How this tool works (no sign-up needed)
- Upload your file above. Each tool shows whether it runs Local (in your browser) or Cloud (encrypted servers).
- Adjust options, then click the Run / Convert / Process button.
- Wait for progress, then download the result. Use Next tools to continue.
If buttons are not visible, enable JavaScript — the interactive workspace loads in your browser.
Free · LocalMerge front/back scans page by page, or reverse page order
Supports application/pdf
Local — your file is processed in your browser and not uploaded to us. No account needed.
What is it?Alternate & Mix PDF is a PDFLean page organization tool: Interleave two PDFs page by page (merge front/back scans) or reverse page order locally without uploading files.
TL;DR: Interleave two PDFs page by page to merge front and back scans, or reverse the page order of a single file. Everything runs locally in your browser — your file is never uploaded and is cleared upon closing the page; requires exactly two files for alternating mode (recommended ≤ 10MB per file).
Measured: ~23 ms median on a typical sample — full benchmark table below.
About this tool
Interleave two PDFs page by page (merge front and back scans), or reverse the page order of a single PDF. Everything runs locally in your browser's memory — free, no account required, and files never leave your device (handles files, recommended ≤ 10MB per file for smooth processing).
Measured performance benchmarks
| Sample | Input | Output | Median time | Size change |
|---|---|---|---|---|
| Reverse page order (60 pages) | 160 KB | 158 KB | 23 ms | −1% |
Measured locally in your browser (isomorphic production code; samples are programmatically generated text PDFs, median of 5 runs). Real-world image-heavy PDFs differ — see the on-page limits.
How to use
Upload two PDF scans for front and back sides (or a single file to reverse)
Adjust file order if needed; keep "Reverse order" checked if the back scan is inverted
Click "Alternate mix" (or "Reverse order" for a single file)
Download your reorganized PDF result
FAQ
Will my file be uploaded?
No. Everything runs locally in your browser — your file is never uploaded and is cleared upon closing the page.
Are there any limits?
Alternating mode requires exactly two files, with file sizes recommended at ≤ 10MB for smooth local processing.
Can I choose the processing order?
Yes. Files are displayed as cards; use the up/down buttons or sort by name to reorder, and optionally check "Reverse order" for the second file.
Can I process multiple files in bulk?
A single tool page handles one task at a time; for bulk work use the Batch Processing workflow and add this tool as a step to run a whole set at once.
Is the processed file still editable?
The result is a reorganized new PDF; the original files remain unchanged and can be re-processed at any time.