Keep a copy before editing
Opening and saving CSV in a spreadsheet can change more than the column you intended to edit. Codes may lose zeros, long references may be rounded, and date-like labels may be rewritten. A saved original lets you distinguish a display change from a change in the exported data.
A six-cell comparison example
The synthetic original contains two data rows with three fields: code, tracking ID and date label. Its edited companion deliberately changes all six data cells. Choose the comparison example to see the original and edited values side by side. These changes are authored examples of possible data loss, not a measurement of a particular Excel version.
What the comparison means
This release compares parsed strings at the same row and column position, including the header. It counts changed, added and removed cells, and displays up to the first 80 differences. It compares the entire accepted file, not just the preview. CSV quoting and line-ending differences that leave the same parsed values do not count as data changes. Whitespace inside a cell does count.
Keep the row order the same
This is not a database join or a comparison by product ID. Sorting, inserting a row or reordering columns shifts positions and can generate many differences. For a meaningful before-and-after check, export both files in the same order. If that is impossible, use a keyed diff in a database or data-analysis tool.
Use the result safely
- Inspect the original CSV and confirm its preview.
- Select the edited CSV saved by Excel. XLSX comparison is not supported in this release.
- Review the total changes and the sampled differences.
- If unexpected values changed, return to the untouched export and make a protected XLSX before repeating the edit.
The tool does not merge the files or overwrite either source. Downloading the protected workbook always uses the original file, not the edited comparison file. A zero-difference result means the parsed cell strings match; it does not establish that the data is correct for your business.
Read Microsoft’s explanation of automatic numeric conversions for the source of several common changes.