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Data Reconciliation Report

Compare unique key sets and selected control totals across two CSV tables, without row-level differences.

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How this works

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Showing an example. Edit to see your own.

Paste a CSV with a heading row. Up to 100,000 data rows, 500 columns and 2,000,000 cells.

The second table. Each table keeps its own key column name, so the two headings do not have to match.

The heading of the unique, nonblank key column in the left table.

The heading of the unique, nonblank key column in the right table.

Comma-separated headings in the left table. Leave both column boxes empty for a key-only report.

Comma-separated headings in the right table. The two lists must name the same number of columns; the heading names may differ.

Case-insensitive matching refuses two keys that fold to the same value instead of merging them.

The same delimiter is used to read both tables.

A report cell whose first visible character is = + - or @ receives an apostrophe in the download. Turn it off to keep the raw value.

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How to use Data Reconciliation Report

  1. Paste the two CSV tables and enter their key columns.
  2. Enter each table’s unique text key and select numeric headings independently on the two sides.
  3. Run the reconciliation and inspect key counts and total differences.
  4. Export the report and investigate unmatched keys in your source tables.

Example: Data Reconciliation Report

Compare keys and one numeric amount.

You add
Left: id,amount 1,10 2,20. Right: id,amount 2,21 3,30. Both key headings: id; both numeric-column lists: amount.
You get
Key 2 is shared; key 1 is missing on the right and key 3 is unexpected. Numeric totals are 30 and 51, giving right minus left = 21.

Options

Left and right key headings
Each table names its own unique nonblank key column. Case-insensitive matching refuses keys that collapse to the same value within one table.
Numeric-column lists
Pair the left and right headings in the same order, even when their names differ. Leave both lists empty for a key-only report; numeric totals require supported numeric values.

Supported inputs and limits

Each table is limited to 20 MiB, 100,000 records, 500 columns and 2,000,000 cells. Keys must be unique and nonblank; they are text, so leading zeroes matter. Totals accept unambiguous finite decimal values with exact decimal arithmetic. This report does not compare matched rows field by field or establish that the underlying records are correct. Numeric cells use plain decimal spelling with up to 30 integer digits and 20 fraction digits. Blank numeric cells are skipped and counted; blank keys are refused. The CSV includes every key status while the text view limits each key list to 50 entries.

Where your input is processed

This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.

A matching key does not mean every field matches

The report identifies shared, missing and unexpected keys and compares selected numeric totals. It does not assert equality of every nonnumeric field or merge the two datasets. Use the row evidence to investigate the specific differences you care about.

Totals can conceal offsetting differences

A total can match while individual records differ, or differ because a key exists on only one side. Read the key categories alongside the arithmetic. The total difference is right minus left; it is not a cause or an automatic correction instruction.

Questions about Data Reconciliation Report

Does a matching key prove the row values agree?

No. It proves only that the key exists on both sides. Use a row-comparison tool when you need field-level differences.

Can the numeric headings differ between tables?

Yes. Enter the numeric headings separately on the two sides, in the order you want them paired. Totals are calculated independently, and the difference is right minus left.

Can a number with currency signs be totaled?

Only the numeric form documented by the fields is accepted. Remove ambiguous separators or currency text before calculating a control total.

Project manager: Tony Hines · Content updated 4 October 2026 · Report a problem

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