CSV Validator
Catch the problems that break imports: a row with one field too many, a quote that never closes, two columns with the same header. Delimiter is detected automatically.
When does a CSV field need quotes?
RFC 4180 has one core rule: if a field contains the delimiter, a double quote or a line break, wrap it in double quotes and double any quotes inside. Type a value and watch the row that gets written.
1,"Portland, OR",active
- contains the delimiter (,)
- contains a double quote, so each " is doubled to ""
- contains a line break
- has leading/trailing spaces (quoting keeps them; not required by RFC 4180, but many parsers trim)
Quotes required.
Written row, exactly: 1,"Portland, OR",active
How it works
CSV has a short standard, RFC 4180: fields are separated by a delimiter, and any field containing the delimiter, a quote or a line break must be wrapped in double quotes, with inner quotes doubled.
Most broken files break that last rule, or come from a spreadsheet exported with a semicolon delimiter (common in European locales).
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Questions
Why does my CSV have the wrong number of columns?
Usually a value contains a comma but is not quoted, so it is split into two fields. Wrap such values in double quotes.
Which delimiters are supported?
Comma, semicolon, tab and pipe, detected automatically. You can also force one.