CSV Diff — Compare Two CSVs by Key

When to use CSV Diff

• Track product catalogs: dump this week's price list vs last week's — see which prices changed.
• Database migrations: export old + new tables → check missing rows and schema changes.
• Audit data imports: before/after importing a CSV into the DB — verify row counts.
• HR / payroll: this month's roster vs last month's — who joined, who left, who got a raise.
• Finance reconciliation: compare transaction logs from 2 sources (bank + accounting).

How it works

The tool matches rows between A and B by a key column (first column by default). Then:

• Added: rows in B but not in A.
• Removed: rows in A but not in B.
• Changed: same key in both but cell values differ.
• Unchanged: same key, every cell matches.

For changed rows, the tool highlights which cells changed (red strikethrough for the old value, green for the new).

Tips

• Pick the right key column: ID, SKU, email — anything unique. Avoid names (can collide).
• Composite keys: the tool only supports a single column. For composite keys, pre-build a combined column (e.g. user_id-date).
• Excel data: export to CSV with "," delimiter (US/VN) or ";" (EU).
• Privacy: runs 100% in your browser. Sensitive data stays local.