Neatbo.

Statistics calculator

Calculate list mean, median, variance and standard deviation, or exact decimal statistics for a CSV column.

Browser-local processingInputNumber list / UTF-8 CSVOutputJSONUp to 10 MiB per file · File limit: 1
  1. 1Add input
  2. 2Adjust settings
  3. 3Get your result

Tool input and files are processed in this browser without being uploaded.

Your input

Inputs are kept temporarily in this tab when switching tools. Refreshing or closing clears them; large results may need to be regenerated.

⌘ / Ctrl + Enter to run
Input mode

List mode uses floating-point variance; CSV mode preserves exact decimal strings for a selected column.

Paste numbers from a spreadsheet column, or separate values with commas, spaces or line breaks. Do not include headers or thousands separators.

Which standard deviation?
Enter at least one value.
Preparing the tool…

Before you start

Choose a number list for population or sample variance and standard deviation. Choose CSV to analyze one numeric column without converting decimal strings to floating-point numbers; check blank and missing cells before exporting the report.

How to use this tool

  1. Choose number list or CSV column. Paste numbers for a list; for CSV, paste a table or choose one UTF-8 file.
  2. For a list, choose population or sample. For CSV, choose delimiter, header setting and a numeric column; check blank, missing and invalid cells.
  3. Calculate and inspect the result. Copy the list standard deviation or the complete JSON report; download the full JSON. Switching input modes keeps each input in this tab and clears the prior result.

Supported inputs and limits

List: up to 10,000 finite numbers and 100,000 characters; commas, semicolons, whitespace and scientific notation are accepted. No headers, units or thousands separators. Magnitudes must be at most 1e100; nonzero values that underflow to zero are rejected.

List variance and standard deviation use floating-point arithmetic and the selected population or sample divisor. CSV mode provides count, minimum, maximum, sum, mean and median; it does not calculate CSV variance or a maximum-minus-minimum range.

CSV: up to 1 MiB of pasted UTF-8 text or one 10 MiB UTF-8 CSV/TSV/TXT file, 200,000 cells including a header row, and 1,000 columns. Headers must be unique and nonempty when used; every row must have equal width.

CSV numeric cells accept signed decimals or scientific notation: at most 110 characters per token, 100 coefficient digits and an exponent of at most three digits with magnitude at most 100. Blank cells are counted separately; exact, case-sensitive missing markers are optional (up to 20 markers, 100 characters each and 2,048 characters in the marker input).

CSV minimum, maximum, sum and median are exact decimal strings. The mean is rounded half away from zero when required to at least 18 decimal places, or the largest input scale if greater; meanRounded and meanDecimalPlaces record this. Five original numeric records are previewed, with all statistics and counts in the JSON report. Processing stays in this browser.

Worked example

Example input

2,4,6
Example options
{"population":"population"}

Example output

{
  "count": 3,
  "mode": "population",
  "divisor": 3,
  "sum": 12,
  "min": 2,
  "max": 6,
  "range": 4,
  "mean": 4,
  "median": 4,
  "variance": 2.6666666666666665,
  "standardDeviation": 1.632993161855452
}

When something does not work

For a list, remove labels and units and enter at least two values for sample statistics. For CSV, check UTF-8, delimiter, headers and row widths, select a column, and correct invalid cells or declare exact missing markers.

Frequently asked questions

Should I choose population or sample?

Choose population when the list contains every value in the group you want to describe. Choose sample when the list is a subset used to estimate a larger group. Sample variance divides by n − 1 and requires at least two values.

How do list and CSV precision differ?

The number list retains floating-point variance and standard deviation. CSV minimum, maximum, sum and median are exact decimal strings, including integers beyond JavaScript’s safe range. CSV means may be rounded, including finite means requiring more decimal places than the chosen scale; the report marks this explicitly.

Can I use CSV without a header or with missing values?

Yes. Select no header and choose the generated column number. Surrounding whitespace is trimmed before numeric and missing-marker matching; marker matching is case-sensitive. Blank cells are counted separately. Other text blocks calculation until declared as a missing marker. Original logical record numbers and up to five valid raw values appear in the preview.

Does CSV mode also calculate variance?

No. CSV mode reports count, minimum, maximum, sum, mean and median. Use the number-list mode when floating-point population or sample variance is suitable.

Is my input sent to a server?

No. Values are processed in your browser. Save the JSON you need before leaving the page.

Documentation & further reading

CSV and JSON guide: compare, join, pivot and convert →Calculation guide: units, fractions, statistics and rounding →CSV comparison, joins and pivots: check records before reporting →Time zones, workdays and rounding: explain calculation results →

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