Compare two Excel lists
Find new, missing and changed rows in CSV or XLSX files. Match columns by an ID or a combined key; duplicate keys stay visible for review.
Preparing your tool…
Read the practical guide and worked example
How to use it
- Open the left and right CSV/XLSX files and select one sheet from each.
- Map corresponding columns and choose one or more key columns.
- Review changed values, entries present on only one side, and duplicate or empty keys.
- Download the Excel report with source rows and original old/new values.
The examples move ID 0013 to a different row and change its amount from 20 to 25. ID 0014 appears twice on the left and is reported as ambiguous rather than paired arbitrarily.
Details & limits
CSV/XLSX up to 5 MiB each; combined comparison up to 100,000 input cells and 10,000 rows. Keys remain exact unless normalization is selected. Duplicate keys are not paired automatically.
What happens when a key occurs more than once?
The matching rows are reported as ambiguous. The tool does not pick one silently. Add another key column or correct the duplicates in the source. By default, 0012 and 12 remain different; optional trimming or case normalization changes comparison only.