CSV Reconciliation
Compare two table versions by a stable key. Separate added, removed and changed records without confusing row movement with edits.
1. Set up your input
Use stable, unique IDs. Key names must exist in both headers. Duplicate or blank keys stop the comparison rather than guessing which records belong together. Limits per input: 3,000 rows, 80 columns, 30,000 cells.
2. Review & export
Ready. Try the example to see how it works.
Using CSV Reconciliation
Compare two table versions by a stable key. Separate added, removed and changed records without confusing row movement with edits.
- Start with the working example to explore the workflow, or add your own inputs.
- Choose the options, build a preview and review the result table and notes.
- Copy or download the output. When inputs change, build a fresh preview before exporting.
Example
Use stable, unique IDs. Key names must exist in both headers. Duplicate or blank keys stop the comparison rather than guessing which records belong together. Limits per input: 3,000 rows, 80 columns, 30,000 cells.
Questions & answers
Does changing row order count as an edit?
No. Records are paired by the selected key columns regardless of order.
Can I use more than one key?
Yes. Enter column names separated by commas. Their values form a composite string key. Column names containing commas cannot be selected as keys here.
What happens with duplicate IDs?
The comparison stops. Choose additional key columns or fix duplicate and blank keys first.
Are leading-zero IDs kept?
Yes. Values are strings; 001 and 1 are different unless you change the source data.
Can the columns be reordered?
Yes. Columns are paired by exact header name. Added or removed columns are reported on paired records.
Is the exported CSV the merged dataset?
No. It is a change report. Added and removed records are JSON arrays in source header order; the JSON report also contains those headers. Formula-like CSV cells receive a leading apostrophe for spreadsheet safety.
Is my input uploaded for processing?
Processing runs in a local browser worker with no input upload and no account. Website advertising and analytics are described in the privacy information.
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