CSV Viewer

View a CSV as a table — and find the rows that do not line up.

Your CSV

Read in your browser

CSVRead in your browser — never uploaded

Delimiter

How this reads your output

The file is parsed to a table and checked before it is drawn. The delimiter is guessed by consistency across the first ten lines rather than by counting one, which is what stops a European export full of decimal commas from being read as comma-separated. Quoted fields are handled properly, including newlines inside them — which is why a CSV cannot be parsed by splitting on line breaks, however tempting. Then every row is compared against the header: any row with a different number of fields is highlighted, because a row shifted one column left looks exactly like a correct row and nothing downstream will notice.

What the results mean

Ragged rows: Rows whose field count differs from the header. Almost always an unquoted delimiter inside a value, and the most consequential fault a CSV can have.
Unterminated quote: An opening quote with no close, so everything after it was read as a single value. A literal quote inside a quoted field has to be doubled.
Duplicate headers: Two columns with the same name. Most parsers keep the last and silently drop the other.
Header looks like data: Every cell in the first row is numeric, which usually means the file was exported without a header and a record is being consumed as one.

Common problems and fixes

The columns are all in one: The delimiter guess was wrong. Set it manually — semicolon and tab are the usual answers for exports from European spreadsheets and databases.
Some rows are highlighted red: Those rows have a different number of fields than the header. Find the offending value — usually one containing a comma that was not quoted — and quote it at the source.
Accented characters look wrong: The file is probably not UTF-8. Re-export it as UTF-8 from whatever produced it; browsers assume UTF-8 and cannot reliably guess otherwise.
Numbers sort in the wrong order: They should not — columns where every value is numeric sort numerically. If they are sorting as text, some cells contain a stray space or currency symbol.

Frequently asked questions

Why does my CSV have rows with the wrong number of columns?

Something in a value contained the delimiter and was not quoted. "Smith, John" written without quotes becomes two fields, and every value after it in that row shifts one column left — the address lands in the phone column, and nothing throws an error. This is why the tool leads with the count rather than quietly padding the rows, which is what most viewers do.

How do I know which delimiter my file uses?

The tool reports the one it detected, and you can override it. Detection compares candidates across several lines and prefers the one whose count is most consistent, because a single-line count picks the comma in a semicolon-separated file full of decimal numbers.

Is my file uploaded anywhere?

No. It is read by your browser with the File API and parsed in the page. CSV exports are usually customer lists, order histories or exported databases, which makes this the wrong category to trust an upload form with.

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