Which CSV dialect is supported?

RFC 4180-compliant: double-quoted fields can contain newlines, commas, and escaped quotes (`""`). Delimiter is auto-detected (comma / semicolon for European CSV / tab for TSV / pipe), and there is a toggle to force the first row as a header.

How are missing values detected?

Blank cells, `null` / `NULL`, `NA` / `n/a`, and `NaN` are treated as missing and excluded from all statistics. Unique counts and numeric stats only consider non-missing values.

How is column type inferred?

If every non-missing value parses as a number, the column is `numeric`; if none do, `text`; mixed gives `mixed`; all-missing yields `empty`. Mixed columns still show mode and average length, but numeric statistics are not reported.

Are thousands separators recognized?

Yes — commas are stripped before numeric parsing, so `1,234.56` parses as a number. In comma-delimited CSV you'll need to quote such values (e.g. `"1,234.56"`) so the parser doesn't split them.

Does it scale to huge CSVs?

Tens of thousands of rows / a few MB run fine in the browser. Multi-million-row files aren't realistic for a browser tool, but everything stays local — no uploads.

What is the numeric precision?

IEEE 754 double precision (JavaScript's number). Display is formatted to 4 fractional digits, but the downloaded TSV emits the raw internal values.

Is my data sent to a server?

No. CSV parsing and statistics run entirely in your browser; neither your input nor the downloaded TSV ever leaves the page.

Back to Developer

CSV stats — per-column count / unique / mean / median / stddev

Paste or drop a CSV and instantly see per-column row count, unique values, missing values, and inferred type. Numeric columns show min / max / mean / median / stddev / sum, text columns reveal the top mode and average length. RFC 4180-compliant parser (double-quote escapes), and the delimiter (comma / semicolon / tab / pipe) is auto-detected. Header row toggle plus empty / NULL / NA recognition as missing. Your raw data never leaves the browser.

developerextractcount

How to use

Paste CSV or TSV into the input box and the tool instantly detects the header row, then computes count, unique value count, missing count, and type (numeric / text / mixed / empty) for every column. Numeric columns also show min / max / mean / median / stddev / sum, and text columns reveal the mode (most frequent value) and average length. Delimiter (comma / semicolon / tab / pipe) is auto-detected (manual override available). Export the summary as TSV via Copy or Download.

FAQ

Which CSV dialect is supported?: RFC 4180-compliant: double-quoted fields can contain newlines, commas, and escaped quotes (`""`). Delimiter is auto-detected (comma / semicolon for European CSV / tab for TSV / pipe), and there is a toggle to force the first row as a header.
How are missing values detected?: Blank cells, `null` / `NULL`, `NA` / `n/a`, and `NaN` are treated as missing and excluded from all statistics. Unique counts and numeric stats only consider non-missing values.
How is column type inferred?: If every non-missing value parses as a number, the column is `numeric`; if none do, `text`; mixed gives `mixed`; all-missing yields `empty`. Mixed columns still show mode and average length, but numeric statistics are not reported.
Are thousands separators recognized?: Yes — commas are stripped before numeric parsing, so `1,234.56` parses as a number. In comma-delimited CSV you'll need to quote such values (e.g. `"1,234.56"`) so the parser doesn't split them.
Does it scale to huge CSVs?: Tens of thousands of rows / a few MB run fine in the browser. Multi-million-row files aren't realistic for a browser tool, but everything stays local — no uploads.
What is the numeric precision?: IEEE 754 double precision (JavaScript's number). Display is formatted to 4 fractional digits, but the downloaded TSV emits the raw internal values.
Is my data sent to a server?: No. CSV parsing and statistics run entirely in your browser; neither your input nor the downloaded TSV ever leaves the page.

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