Understand CSV records before cleanup
By Delete Duplicate Lines Online · Published · Updated
A CSV record is not always one visible line. A quoted field can contain a comma or even a line break. Splitting a CSV file at every comma or newline can silently move values into the wrong columns.
Quoted values are one field
name,city
Alice,"New York, NY"
Bob,"He said ""hello"""The comma in New York stays inside the city field. Doubled quotes represent a literal quote inside a quoted value.
Validate structure first
Use the CSV validator to check quotation and consistent column counts. It cannot establish whether a value is factually correct or matches your business rules.
Be deliberate about headers
When converting to JSON, headers become object keys. They must be unique and non-empty to avoid losing fields. The CSV to JSON tool keeps cell values as strings, preserving leading zeroes such as postal codes.
Clean with a reversible workflow
Keep a source copy, inspect the table preview, apply one cleanup rule and compare the output. Spreadsheet applications may interpret formula-like cells when you open an exported file; review untrusted data before using it there.