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CSV Compare

What actually changed between these two files?

  1. Load file A and file B
  2. Pick the key column(s)
  3. Read the tabs, export what you need

Runs in your browser. Nothing you load here is uploaded or stored.

Step 1

Load file A and file B

A is the "before", B is the "after". Row order never matters.

No file A yet.

No file B yet.

Step 2

Pick the key

The key is what identifies the same record in both files — one column or several together. Columns named like id, key or email are suggested automatically.

Key columns (from file A)
Ignore columns when looking for changes

Useful for timestamps like updated_at that differ on every export.

Step 3

Compare

The classic use: last month's export as A, this month's as B, keyed on id or email. Three tabs later you know who's new, who left, and exactly which fields moved — with the old and new value side by side, ready to paste into an email or a ticket.

Limits

  • Up to 100,000 rows per file.
  • Keys duplicated in either file can't be compared one-to-one, so those rows sit in the duplicate tabs and out of the others — the results never depend on row order.
  • Changes are found in columns both files share (by name); the key and any ignored columns are skipped.

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