CSV Formatter & Validator
Tidy up CSV and catch rows with the wrong number of columns.
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How to use it
Paste your CSV to get it back neatly formatted, with any rows that have the wrong number of columns pointed out. Your data stays on your device.
Paste your CSV data into the box. It works out whether your columns are split by commas, semicolons, or tabs (or you can choose), and gives you back a tidy, consistent version to copy or download.
It also checks every row has the same number of columns as the first one. A row with too many or too few usually means a stray comma inside a value, or two rows got stuck together.
This tool points out problems but doesn’t try to fix them, because a wrong guess is worse than a warning. For automatic clean-up, use the CSV Cleaner.
FAQ
How does it know how my columns are split?
It looks at the first line and picks whichever of comma, semicolon, or tab appears most. You can change it if it guesses wrong.
What’s a row with the wrong column count?
A row with more or fewer values than the first row. It usually means a stray comma or a broken line.
Does it fix broken CSV?
No, it points problems out. Use the CSV Cleaner to fix them automatically.
How it worksFor the curious
The parser follows RFC 4180: a field containing the delimiter, a quote, or a line break is wrapped in double quotes, with inner quotes doubled. It walks the input character by character tracking whether it is inside a quoted field, rather than splitting on commas.
Delimiter detection counts commas, semicolons, and tabs on the first line and picks the most frequent. Semicolons are common from European spreadsheet software that uses the comma as a decimal separator.
A “ragged row” is any row whose field count differs from the first row’s.