How to clean a CSV file
- Choose your file (or try the sample data). Check that the columns look right in the table.
- If the first row is not made of column names, untick “First row contains column names”.
- Pick a cleaning step, read the preview, and apply it. Repeat for other steps.
- Use Undo if a result isn’t what you expected, then download the cleaned CSV.
What counts as a repeated row?
By default a row is a repeat when every cell matches another row exactly. You can compare only some columns (for example, an email address) and decide whether to keep the first or the last copy. Options let you ignore capitalisation and surrounding spaces.
Postcodes, SKUs and barcodes in Excel
Excel often drops leading zeros (02134 becomes 2134) and shows long numbers in scientific notation (1.2345E+12). “Protect identifiers” flags the columns that look affected and adds leading zeros back when you give the intended length. It cannot know the original length, and it cannot recover digits that were already rounded away. Numbers above 15 digits are flagged for review, never guessed. To keep identifiers intact in Excel, open the file with Data → From Text/CSV and set those columns to Text. You can try this on the identifier sample.
Spreadsheet formulas in CSV files
Some spreadsheet programs run cells that begin with =, +, - or @ as formulas when a CSV is opened. Riluko never executes cell contents, and leaves your values unchanged unless you turn on “Protect against spreadsheet formulas”, which adds an apostrophe so those cells display as text.
Limits
Everything runs inside your browser, so very large files depend on your device’s memory. Files up to 25 MB are accepted. Cell contents are always shown as plain text.