Spreadsheet Data Quality Checker
Measure blanks, outer whitespace, repeated values and case inconsistencies that can interfere with matching and reporting.
Cleanup
Find Duplicate Rows in a Spreadsheet
Find every repeated key in a CSV, TSV or XLSX file and export the affected rows for review or correction.
Processing boundary: text and files are handled only for this request. Original files are not overwritten. Generated CSV downloads use expiring private tokens.
What this tool does
Duplicate records create false totals, duplicate payments, double-assigned assets and misleading headcounts. This tool indexes a selected key column and lists every row belonging to a repeated normalized key. It does not delete anything from the source file. Instead, ReconNimble creates a review report showing the duplicate key, the number of occurrences and a serialized preview of each affected row. This makes the tool useful before an import, lookup, payroll run or reconciliation where uniqueness matters.
How to use it
- Choose a CSV, TSV or XLSX file.
- Enter the exact key header or leave it blank to use the first column.
- Review the duplicate-key count and download the affected rows.
Limitations and review points
A repeated value can be valid in a non-key column. Choose a field that should genuinely identify a record, or use the Key Column Finder first.
Frequently asked questions
Does this remove duplicates?
No. It creates a review report and leaves the source file unchanged.
Are case differences treated as duplicates?
Yes. Key matching is case-insensitive and trims repeated whitespace.
Can I use multiple columns as a key?
Composite keys are planned for the full reconciliation workflow in Delivery 2.
Related spreadsheet tools
Key Column Finder
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Remove repeated lines while preserving the first occurrence and the original readable capitalization of each unique value.