CSV Diff Comparator — Free Online Tool
Compare two CSV files or pasted data and see exactly which rows differ. Normalizes quoting and whitespace before comparison so formatting differences don't show as content differences. Uses papaparse for CSV parsing and jsdiff for line-level comparison.
100% client-side. No uploads. Your data never leaves your browser.
How to use CSV Diff Comparator
- Paste CSV A (original) and CSV B (modified).
- Click Compare.
- Green rows are added, red rows are removed.
- Check the row count summary above the diff.
Frequently Asked Questions
Does this handle quoted fields with commas?
Yes. The parser handles RFC 4180 compliant CSV including quoted fields with commas, newlines, and escaped quotes.
What does 'normalize before diff' mean?
The tool re-serializes both CSVs with consistent quoting before diffing, so differences in quoting style don't appear as changes.
Can I compare large CSV files?
Up to 10 MB per input. For very large files with many differences, the diff may be slow to render.
Related tools
Related reading
Browse all free tools · theproductguy.in