CSV Compare — Offline Export Reconciliation

Two CSV exports, match by key, report stays on this machine.

CSV Compare is an offline csv compare: a csv diff to compare csv files and compare two csv files on this machine. Use it for csv reconciliation and export reconciliation — reconcile csv exports, key match csv rows, and list unmatched records from a stripe csv, shopify csv, bank export csv, bookkeeping csv, or data migration csv. This local csv tool is an offline reconciliation tool for transaction matching. It does not connect to banks.

Who it is for

Bookkeepers, shop operators, and anyone reconciling two UTF-8 exports: Stripe vs books, Shopify vs warehouse, bank vs ledger, or before/after migration.

Four steps

1. Open CSVCompare.html in a desktop browser. Graphical compatibility and file-picker downloads are unverified.
2. Paste UTF-8 CSV text or select two local CSV files.
3. Set the key as a JSON array (exact ID or ordered composite). If names differ, fill the after-key array in the same order.
4. Compare. Review matched / only-A / only-B / changed fields, then export JSON or text if you need a copy.

Examples

In-app buttons: Load example (id=001 apple qty 2→5, plus one added / one removed / one unchanged); Try different key names (sku+warehouse → product_code+location); Try duplicate-key diagnosis (id=001 blocked, before records 2 and 3, no silent match).

Zip

CSVCompare.html, LICENSE.txt, PRIVACY.md, README.md, VERSION.txt. Examples are in-app buttons, not separate CSV files.

Compares two local CSVs → matched / only-A / only-B / changed fields. Does not certify books or connect to banks.

Exact case-sensitive strings only. Leading zeros and whitespace remain significant. No fuzzy matching, automatic editing, arbitrary value-column mapping or import guarantee. Limits: 2 million combined input characters, 2 MB per selected file, 10,000 combined data records, 200 columns per file and 5 million characters per exported report. Review results before relying on them.

Version 0.3.0 candidate: 31 core checks and 19 simulated interface checks pass. Actual graphical browser compatibility and actual browser downloads remain unverified. This is not a fully browser-tested release. No guaranteed future updates.