How do I compare two CSV or JSON exports by key?

Load two CSV or compatible JSON exports, choose a shared identifier, then review missing records, duplicate keys, and field mismatches for matching records.

Are my reconciliation files uploaded?

No. Selected reconciliation files are processed locally in your browser and are not uploaded to the Ops Control HQ backend.

What happens with missing rows or duplicate keys?

Keys found on only one side are reported as missing from the other export. Duplicate keys are flagged because they can make a one-to-one comparison ambiguous.

When should reconciliation become a recurring operating control?

When the same exports are compared repeatedly, define an owner, cadence, exception rule, evidence requirement, and escalation path so discrepancies become a managed operating control.

LOCAL-FIRST DATA CONTROL

Compare two CSV/JSON files by key—free, no file upload.

Use this browser-local CSV diff and reconciliation tool to find added or missing records, duplicate keys, and changed cells. You can also audit one CSV or compare compatible JSON exports.

Your files stay local. This page processes selected files in your browser. It does not upload them to an Ops Control HQ backend.

DATASET QA

Audit one export

Useful before imports, reporting, handoffs, CRM cleanup, inventory review, payout reconciliation, or migration work.

CSV or JSON file Optional unique-key field

Choose a file or load the sample dataset.

TWO-FILE RECONCILIATION

Compare two exports

Choose a shared key, then see records missing from either side, duplicate keys, and cells whose values differ.

Left CSV or JSON Right CSV or JSON

Shared key

Load two files or use the sample reconciliation.

How the CSV diff works

Load two exports and choose a shared key such as account_id, order_id, invoice_id, SKU, merchant_id, or ticket_id. The comparison reports records found only on the left, records found only on the right, field-level differences for matching keys, and duplicate keys that can make reconciliation ambiguous.

Common questions

Compare by key: yes—choose a column shared by both files. No upload: selected files are processed locally in your browser. JSON support: compatible record-based JSON exports work too. The tool reports structural differences; it does not decide which source is correct.

WHEN THE DATA PROBLEM IS REALLY A CONTROL PROBLEM

Turn recurring cleanup into an operating routine.

If you keep reconciling the same exports manually, the next useful step is usually ownership, cadence, exception handling, evidence, and a decision rule—not another one-off cleanup.

Operations Starter Kit — $29 Operator Control System — $99 Take the free operations assessment

This tool reports structural data differences. It does not determine which source is authoritative, alter source systems, infer sensitive attributes, or provide accounting, legal, compliance, underwriting, or audit conclusions. Review material discrepancies with the appropriate responsible person.