CSV File Comparison — Find Differences Between Two CSV Files

Compare two CSV files side by side to find added, removed, and modified rows.

File A — Original

File B — Updated

0-based column index used to match rows. Use comma for multiple keys.

Frequently Asked Questions

The tool uses a key column (default: first column) to match rows. Rows with the same key value are compared cell by cell. Rows with a key that exists in only one file are marked as added or removed.

Yes. Enter comma-separated column indexes in the Key Column field (e.g. "0,1" uses both the first and second columns as a composite key). This is useful when no single column is unique.

Green rows were added in File B (new records). Red rows were removed from File A (deleted records). Yellow rows exist in both files but have at least one changed cell value. Individual changed cells are highlighted in amber.

The tool keeps the last occurrence of each key when indexing. If your data has duplicate keys, deduplicate first using the Remove Duplicates tool for more reliable comparison results.

Yes. Click Download Comparison Report to get a CSV file containing all added, removed, and modified rows with their status labelled in the first column. Equal rows are excluded from the report.

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