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ListDiff

Compare CSV files by key

Free table diff for two exports. Match rows on an ID, SKU, or email column—then see which keys were added or removed, and which cells actually changed. The compare stays in your browser.

Free Local processing No signup Match by key

Tool

CSV A (older)
0 rows
CSV B (newer)
0 rows
Updates as you type · first header row is column names

Paste two CSV exports with headers—the table diff updates automatically.

Only need which IDs appeared or disappeared? Extract one column on the CSV ID list workflow or the list compare tool. This page is for cell-level changes on matched keys—not a full Excel workbook highlighter.
Compare lists Find duplicates Compare JSON CSV as ID lists Docs

How it works

  1. Paste or upload two CSV exports. The first row on each side is the header.
  2. Pick the key column if the guess (id / sku / email) is wrong.
  3. Rows match on that key even when the files were re-sorted.
  4. Filter Added / Removed / Changed, then copy stats or the TSV report.

Good for

  • Price or stock updates on the same SKU list.
  • CRM exports where contacts were reordered but IDs stayed.
  • Catalog snapshots: discontinued vs new codes, plus field edits.
  • Private exports—no account, no upload for the compare step.

Quick answers

CSV vs list compare? Use this page when other columns matter. Use list compare when you only care which IDs exist.

CSV vs text? A line-by-line text compare treats a moved row as a huge rewrite. Table compare does not.

Excel .xlsx? Save or copy as CSV / TSV first. This is not a full workbook highlighter.

Huge files? Each side truncates after a few thousand data rows so the tab stays usable.

What is CSV compare on ListDiff?

This tool is a free CSV compare that treats each file as a table: it joins rows on a key you choose, then reports cells that differ. Column order can change; names in the header still have to match.

It sits beside list compare, text compare, and JSON compare. Pick the mode that matches the question so you do not mix membership gaps with cell edits.

Added / removed keys

Keys that exist only in B or only in A—new SKUs vs discontinued codes.

Changed cells

Same key, different value—price, stock, or name shown side by side.

Duplicate-key warning

If an ID appears twice, only the first row is used and you get a short list of duplicates.

When this tool helps

  • Two catalog or inventory dumps with the same ID column.
  • You need “what changed on this SKU,” not only “which SKUs are new.”
  • The files were sorted differently and a text diff is unreadable.

Related tools

Compare lists

Missing / extra IDs after you extract one column.

Find duplicates

Repeated keys inside one export before you trust the join.

SKU list gaps

When you only need discontinued vs new codes.

FAQ

How do I compare two CSV files online by ID?

Paste both sides with headers, pick the key, then read Added / Removed / Changed. Row order does not matter.

Is this the same as comparing two lists of SKUs?

No. List compare answers membership. This page also shows cell edits on matched keys. See CSV compare docs.

Does my CSV leave the browser?

No for the compare step. See Privacy and Is ListDiff safe?.

What if a key appears twice?

Only the first row for that key is compared. Use find duplicates if you need to clean the file first.