Comparison

Compare Two CSV or Excel Files by a Key Column

Compare two spreadsheet files using a selected key and group records into matched, missing, duplicate and conflicting buckets.

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

The quick spreadsheet comparator provides an early version of ReconNimble’s core reconciliation experience. Upload two supported files and identify the key header in each dataset, such as Employee Code, Invoice Number or Serial Number. The tool normalizes key text, groups duplicate keys and labels each distinct key as matched, missing in one source, duplicated or conflicting. It is intentionally conservative: the result preview shows the source rows so a reviewer can verify why a key received its status before downloading the CSV report.

How to use it

  1. Select Source A and Source B.
  2. Enter the exact key header for each file, or leave the fields blank to use the first column.
  3. Run the comparison, review the counts strip and download the exception report.

Limitations and review points

Delivery 1 compares non-key values by column order after removing the key. Advanced field mapping, saved jobs, fuzzy matching and manual resolution are part of Delivery 2.

Frequently asked questions

Can the key column names differ?

Yes. Enter the exact header from each file.

How are duplicate keys handled?

Any key appearing more than once in either file is placed in the Duplicates bucket.

Does the result contain ads?

No advertisements render inside private processing or result actions; advertising is restricted to eligible public content surfaces.

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