How to clean CSV files safely
A practical checklist for headers, duplicates and blank values.
What matters
Start by preserving the original. Normalize headers, trim outer whitespace, identify empty cells, then remove only exact duplicate rows. Review identifiers with leading zeroes before opening them in spreadsheet software.
A safe workflow
- Keep the source unchanged.
- Test on a representative copy.
- Review the output for meaning, not only file size or a green status.
- Record the settings that worked.
Common mistake
Automation can make a wrong assumption repeat faster. Confirm encoding, units, schema meaning or visual quality before applying a result broadly.