Guides / Data cleanup

How to Clean a CSV Before Importing It

A five-minute cleanup pass can prevent broken imports, duplicate records and mysterious totals.

1. Make sure the header row is actually a header

Importers generally expect column names in the first row. Remove title rows, blank lines or report metadata above the real header.

2. Trim whitespace

Values like “Mumbai” and “Mumbai ” can look identical but behave differently in matching and deduplication. Trim leading and trailing spaces before importing.

3. Remove duplicates deliberately

Do not delete similar-looking transactions blindly. Exact duplicate rows are safer to remove automatically; near-duplicates should be reviewed against the source.

4. Check columns and dates

Make sure every row has the expected number of columns and that dates use the format your destination system expects. Keep account or transaction identifiers as text if leading zeroes matter.

5. Preview before you import

Open the cleaned file and inspect a few rows from the top, middle and end. Check totals if the file contains financial data.

Fast option: use the CSV Cleaner & Deduplicator to trim values, remove exact duplicate rows and download a cleaned CSV without uploading the original file.