How to Clean Messy CSV Data
CSV files can contain duplicate records, blank cells, inconsistent dates, extra spaces, and values stored in the wrong format.
1. Preserve the original
Make a working copy before changing the data.
2. Check the structure
Confirm headers, columns, delimiters, and expected data types.
3. Find duplicates
Choose the fields that define the same record before removing duplicates.
4. Check blanks and inconsistent values
Look for missing required fields, spelling variations, capitalization differences, and extra spaces.
5. Check dates and numbers
Mixed date formats and numbers stored as text can cause reporting and sorting problems.
6. Validate the result
Run the CSV through CASSIA's free Data Quality Checker before using it for reporting or analysis.