Why the data becomes misaligned
Spreadsheet tools normally match columns by their exact header text. Small naming differences create new fields, even when the values mean the same thing.
Build a field map first
Choose a standard field such as Name, Phone, Email, or Date. Then map each source header to that standard before rows are combined.
Check ambiguous matches
Automatic matching can save time, but business-specific names still need human review. Confirm every suggested target before exporting.
FIX IT IN YOUR BROWSER
Use the file on your device. Nothing gets uploaded.
Load a sample or choose your own files, confirm the result, and download a clean workbook.
Open the free tool