About CSV Diff
CSV Diff compares two tables. Match rows by a key column such as id or email to find records that were added, removed, or changed regardless of row order — or compare by row position when there is no key. Changed cells are highlighted with their old and new values.
How to use CSV Diff
- Paste or open the original CSV on the left and the updated CSV on the right.
- Confirm whether the first row contains headers.
- Choose a key column to match rows, or compare by row position.
- Select Compare, review the table, and optionally download a CSV report of the differences.
Examples
Customer exports
Match on customer_id to see which customers were added or removed and whose email changed.
Price lists
Compare two supplier price lists by SKU to find changed prices.
Limitations
- Key values should be unique; duplicate keys are reported, and only the first occurrence is compared.
- Columns are matched by header name when headers are present, otherwise by position.
- Values are compared as text, so 1.0 and 1 are different.
Privacy
This tool processes everything locally in your browser tab. Your input is not uploaded to Utilhex or any third party, and it is discarded when you close or reload the page. Read the privacy policy for details.
Frequently asked questions
Is my spreadsheet uploaded?
No. Both files are parsed and compared in your browser.
Which delimiters are supported?
Commas, semicolons, tabs, and pipes are detected automatically.
Can I compare Excel files?
Export each sheet as CSV from Excel, Google Sheets, or Numbers first. Native .xlsx comparison is not supported yet.