DiffCheck

CSV 列统计

粘贴 CSV 数据，立即获得每列统计：数量、空值数、唯一值数、最小值、最大值、均值、中位数、标准差。

What Is CSV Column Stats?

The CSV Column Stats tool analyzes the columns in a CSV file and computes descriptive statistics for each one — instantly, in your browser. Paste any CSV data and click Analyze to see per-column count, null count, unique value count, min, max, mean, median, and standard deviation. Numeric columns receive full statistical analysis; string columns show lexicographic min/max and top value frequencies. No file upload, no server — all processing runs locally.

How to Use the CSV Column Stats Tool

  1. Paste your CSV data into the input field (the first row must be the header row).
  2. Click Analyze to compute statistics.
  3. Review the results table — each row represents one column from your CSV.
  4. Click Details on any column to see the top 5 most frequent values.
  5. Use Load Sample to try the tool with example data.

Features

  • Per-column statistics: count, null count, unique count, min, max
  • Numeric columns: mean, median, and standard deviation
  • Automatic column type detection (number / string / mixed)
  • Top 5 most frequent values per column
  • Null count highlighted in red when non-zero
  • Supports quoted fields and commas inside quotes (RFC 4180)
  • 100% client-side — data never leaves your browser
  • Sample dataset included for quick testing

FAQ

What statistics does the CSV Column Stats tool calculate?

For each column, the tool calculates: total count (rows), null/empty count, unique value count, min, max, mean (average), median, and standard deviation. Numeric columns get full statistical analysis; string columns show min/max lexicographically and top value frequencies.

Is my CSV data uploaded to a server?

No. All processing happens entirely in your browser using JavaScript. Your CSV data never leaves your device and is not sent to any server.

What counts as a null value?

The tool treats empty strings, the literal text "null", and the literal text "NA" (case-insensitive) as null/missing values. These are excluded from statistical calculations like mean, median, and standard deviation.

How does the tool detect column types?

A column is classified as "number" if all non-null values can be parsed as valid numbers. It is "string" if no values are numeric. It is "mixed" if some values are numeric and some are not. Only numeric columns show mean, median, and standard deviation.