How to merge Excel files
- Drop two or more spreadsheets onto the upload area. You can mix
.xlsx,.xls,.xlsm,.odsand.csvfiles. - Choose how to merge under Merge into:
- One workbook, each sheet kept – every sheet from every file is copied into a single workbook.
- One sheet, rows appended – the rows of all files are stacked into one long table.
- Click Merge files and download the combined
.xlsxworkbook.
All merging happens in your browser. Your spreadsheets are never uploaded or stored, so confidential figures stay on your device.
Two ways to combine spreadsheets
| Mode | Result | Use it when |
|---|---|---|
| Keep sheets | One workbook containing all the original sheets as separate tabs | The files hold different kinds of data, or you want to keep each source separate, e.g. one report per department |
| Append rows | One sheet with the rows of every file one after another | The files share the same columns, e.g. monthly exports, survey results or orders from several shops |
Keep sheets is the digital equivalent of putting several workbooks into one folder: nothing is mixed, but everything is in one file. Append rows builds a single dataset that you can sort, filter and analyse with a pivot table straight away, which is often the goal when consolidating regular exports.
Preparing files for appending
Appending rows works best when the data is consistent across files:
- Same column order. Rows are stacked as they are, so column A of every file should hold the same field.
- Same header names. Use identical headings in each file. After merging, check for repeated header rows and delete any you do not need.
- No extra content. Remove titles, notes and totals above or below the table, otherwise they end up in the middle of the merged data.
- Add a source column (for example "Month" or "Store") before merging if you need to know which file each row came from.
Limitations
- The merged workbook focuses on data. Charts, pivot tables, macros and advanced formatting from the source files are not carried over.
- A single Excel sheet holds up to 1,048,576 rows, which is the upper limit for the append mode.
- Very large workbooks are limited by your browser's memory, since processing happens on your device.
Frequently asked questions
Can I merge CSV and Excel files together?
Yes. You can mix CSV, XLSX, XLS, XLSM and ODS files in one merge, and the output is always an .xlsx workbook.
In what order are the files merged?
Files are combined in the order they are listed, so arrange them before merging if the order of sheets or rows matters.
Are formulas kept?
The merge is designed for combining data. Check any formulas in the result, because references to other sheets or files may no longer point to the same cells.