Copy Large Excel Files

A large Excel file, whether it's an existing XLSX workbook that's grown unwieldy or a dataset you need to get into Excel format from somewhere else, needs an efficient approach to copying that doesn't require manual, sheet-by-sheet range selection.

Million by Million Rows Copier copies large Excel files efficiently by loading the source data, XLSX, XLS, or 25 or more other formats, then either walking through Copy Next Chunk for manual paste control, or using Export Everything As to write a complete, multi-sheet XLSX workbook automatically.

Export Everything As handles the sheet-splitting logic for you: a large dataset gets divided into multiple sheets within the output XLSX workbook, each sized according to your chunk size setting, without you needing to calculate boundaries or copy ranges manually.

For a more hands-on approach, Copy Next Chunk builds each piece, with the header row included automatically, ready to paste into a specific sheet if you want direct control over exactly where each portion of the data lands.

Both approaches draw from the same underlying SQLite-backed storage, so whether you're exporting the whole file at once or working through it chunk by chunk manually, the process stays efficient and responsive regardless of dataset size, up to 50,000,000 rows.

Everything runs locally on your PC, aside from a one-time license check. Loading, chunking, and exporting all happen offline, with your Excel data never uploaded anywhere. Data analysts and engineers moving large extracts between tools, database administrators handing off query results, finance and accounting teams transferring big ledgers, operations and reporting staff assembling data from many sources, and anyone who has ever tried to paste more rows into Excel than it was willing to accept, all use the same underlying workflow. Virtual rendering keeps the loaded-data view smooth even at the upper end of the app's capacity, and every worker thread runs its own SQLite connection in WAL mode, so nothing here depends on your PC having an unusual amount of memory to spare.

1. Install Million by Million Rows Copier on your Windows PC.
2. Paste your Excel data with Ctrl+V or load an XLSX or XLS file.
3. Choose Export Everything As for an automatic multi-sheet workbook.
4. Or click Start Copying Out and use Copy Next Chunk for manual control.
5. Set your chunk size to determine how sheets are divided.
6. Review the resulting workbook or manually pasted sheets.
7. Open the output folder to find your saved files.
8. Repeat the process for additional large Excel files as needed.
9. Use Re-copy Current Chunk if your clipboard gets overwritten mid-paste.
10. Click Open Output Folder to review everything you've saved so far.

• Export Everything As builds a complete multi-sheet workbook
• Automatic sheet-splitting based on your chunk size
• Copy Next Chunk for manual, hands-on paste control
• Header row included automatically in every chunk
• SQLite-backed storage keeps both approaches efficient
• Handles Excel files up to 50,000,000 rows total
• Runs fully offline aside from a one-time license check
• One-time purchase for Windows, with Gumroad license activation
• Choose your own output folder, or use the default under My Documents
• Works with files on local drives, external drives, and network shares