How to use
- Open the old and new files.
- Pick a key column (such as ID) or compare by row number.
- Filter by Added / Removed / Changed and export the report.
Worked example
Old file: IDs 1 (Ann, 10), 2 (Bob, 20), 3 (Cy, 30). New file, reordered: 3 (Cy, 30), 1 (Ann, 15), 4 (Di, 40). Matching on ID gives 1 added (4), 1 removed (2), 1 changed row with one changed cell (Amount 10 to 15) and 1 unchanged. Compared by row position, the same files show 3 changed rows and 9 changed cells.
Supported formats and limits
| Input | CSV, TSV, XLSX, XLS, ODS |
|---|---|
| Output | Diff report (CSV/XLSX) |
| Engine | Key-based row matching with per-cell comparison and optional numeric tolerance |
Limitations
- Duplicate keys are reported and compared in order of appearance.
- Only columns present in both files are compared cell by cell; extra columns are listed.
Questions
Does changing row order count as a difference?
Not when you match by a key column such as ID: rows are paired by key, so reordered rows compare as unchanged. When you compare by row position, row 1 is compared with row 1, so reordering shows up as changed rows.
How is the key column chosen?
When both files are opened, the tool suggests a column found in both whose values are unique and non-blank, preferring names such as ID, SKU or Email. You can choose one or more key columns yourself or switch to row position.
What happens with duplicate keys?
They are listed in a warning with their counts, and rows sharing a key are paired in order of appearance: the first with the first, the second with the second.
Are 1.50 and 1.5 treated as different?
No, by default numbers are compared by value and surrounding spaces are ignored. You can set a numeric tolerance, ignore case, or compare text exactly.
Guides
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