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#064 · Merge Split & Organize Tool

Combine CSV Files

Select two or more CSV or TSV files. Choose whether to align columns by header, keep a source-file column, and retain empty rows, then combine the data.

Office File Tool

Local browser processing
row
rows
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How to use this office tool

  1. Select or drop the supported files.
  2. Review the detected sheet and adjust the operation-specific options.
  3. Process the file, inspect the limited preview and output counts, then download the new result.

What this tool does

Rows are appended under a shared header; header-aligned mode maps values by column name.

Files with different delimiters are detected independently. Review columns that occur in only some files.

CSV and TSV inputs are supported. The result can be downloaded as CSV, TSV, JSON, or XLSX.

Supported formats

CSV and TSV inputs are supported. The result can be downloaded as CSV, TSV, JSON, or XLSX.

FormatUse
XLSX / XLSWorkbook data and formulas where applicable
CSV / TSVDelimited tabular data with detected quoting

Tips for better results

  • Keep a copy of the original before changing production data.
  • Use a clear, unique header row.
  • Check identifiers, dates, formulas, and a sample of output rows.

FAQ

Does Combine CSV Files upload my spreadsheet?

No. Processing happens in your browser, and the selected file is not sent to Calloffice.

What happens to formulas when I use this combine tool?

Formula cells are preserved where the selected operation can retain them, but the browser does not reproduce Excel's full calculation engine.

Can I use large files with Combine CSV Files?

Yes, within your browser's available memory. The preview is capped, and very large workbooks may take longer or need to be split first.

How are dates, IDs, and leading zeros handled?

The tool uses displayed spreadsheet values where appropriate and avoids intentional numeric conversion unless the selected operation requires it. Review identifier columns after export.

What should I check before using the downloaded file?

Check the preview, output counts, headers, and a few representative rows. Keep the original file until the result has been verified.

Processing summary

StageBehavior
InputMerge Split & Organize
PrivacyLocal browser processing
DownloadNewly generated result file

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