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Compare CSV Files by Multiple Keys, Ignore Row Order
Compare local UTF-8 CSV files using one or more key columns. Filter added, removed and changed rows, preserve original values and download a complete difference report.
Compare two CSV files
LOCALFiles stay in this browser. Each file can be up to 2 MiB, 10,000 data rows and 100 columns. UTF-8 only.
Choose two files, set the comparison, then run it to see differences with source line numbers.
Getting started
Choose two CSV files, a delimiter and one or more matching columns. Select fields to compare, optionally ignore surrounding whitespace or letter case, then filter the preview and download the full report. Whole-row mode counts repeated rows.
Before you use the result
Local UTF-8 files only, up to 2 MiB, 10,000 rows and 100 columns each. Every key part must be nonblank and the combined key unique after the selected rules. No numeric or date equivalence is inferred.
Try an example
An old export has ID 000123 before 000124, while the new export reverses them and changes one status. Key comparison reports only that status change.
How it works
CSV cells stay strings. Key mode matches explicit tuples of selected fields; whole-row mode compares row multiplicities. Matching is exact by default, optional text rules never change the reported source values, and no input is uploaded.
Frequently asked questions
Compare two local CSV files without row-order false alarms. See added, removed and changed records while keeping IDs, dates and leading zeros as text.
How do I use Compare CSV Files by Key or Row?
Choose two CSV files, a delimiter and one or more matching columns. Select fields to compare, optionally ignore surrounding whitespace or letter case, then filter the preview and download the full report. Whole-row mode counts repeated rows.
Does this tool upload my data?
Inputs and files are processed in your browser. Page-view analytics do not contain your tool input.
What should I check before using the result?
Local UTF-8 files only, up to 2 MiB, 10,000 rows and 100 columns each. Every key part must be nonblank and the combined key unique after the selected rules. No numeric or date equivalence is inferred.