Simple Statistics Calculator

Example Data Table

The table below shows a sample dataset and a few reference outputs you can compare after running the calculator.

Case	Dataset	Mean	Median	Sample standard deviation	Q1	Q3
Quiz scores	12, 15, 15, 18, 20, 22, 22, 24, 30	19.78	20.00	5.49	15.00	22.00
Daily output	45, 50, 48, 52, 49, 55, 60	51.29	50.00	4.96	48.50	53.50
Study hours	2, 3, 4, 4, 5, 6, 8	4.57	4.00	1.99	3.50	5.50

Formula Used

Mean: Mean = Sum of all values / Number of values.
Median: Median is the 50th percentile of the sorted dataset.
Mode: Mode is the most frequent value or values.
Range: Range = Maximum - Minimum.
Population variance: σ² = Σ(x - μ)² / n.
Sample variance: s² = Σ(x - x̄)² / (n - 1).
Standard deviation: Square root of variance.
Percentiles and quartiles: Calculated with linear interpolation on sorted data using position = (n - 1) × p.
IQR: IQR = Q3 - Q1.
Coefficient of variation: CV = (Standard deviation / Mean) × 100.
Standard error: SE = Sample standard deviation / √n.
Confidence interval: Mean ± z × SE, using the selected confidence level.
Geometric mean: nth root of the product of positive values, computed from logarithms.
Harmonic mean: Number of values / Sum of reciprocals, valid when values are non-zero.

How to Use This Calculator

Enter numeric values into the dataset box. You can separate values with commas, spaces, semicolons, vertical bars, or line breaks.
Add a dataset name if you want cleaner export filenames and report labels.
Choose decimal places, a custom percentile, confidence level, and whether sample or population measures should be highlighted.
Keep the invalid-token option enabled if your pasted list may include text labels or stray symbols.
Press Calculate Statistics to show the result block below the header and above the form.
Review the summary table, frequency table, and sorted data preview for a full descriptive overview.
Use the CSV button to save a flat report and the PDF button to download a printable snapshot of the result panel.

Frequently Asked Questions

1) What does this calculator measure?

It measures central tendency, spread, quartiles, percentiles, frequency, variation, and shape. You can also review confidence intervals, export reports, and inspect cleaned sorted values.

2) What separators can I use in the dataset box?

You can use commas, spaces, semicolons, line breaks, or vertical bars. This makes copying values from notes, spreadsheets, reports, or classroom material much easier.

3) What is the difference between sample and population results?

Population formulas divide by the full count. Sample formulas adjust with n minus one, which is commonly used when the data represents only part of a larger group.

4) Why might the geometric mean show as not defined?

The geometric mean needs strictly positive values. Zero or negative values make the product-based measure unsuitable, so the calculator leaves that result undefined.

5) Why might the harmonic mean show as not defined?

The harmonic mean depends on reciprocals. If any value is zero, division by zero appears, so the calculator marks the harmonic mean as undefined.

6) How are quartiles and percentiles calculated here?

The calculator sorts the dataset and uses linear interpolation between neighboring positions. This gives smooth percentile estimates for both small and large datasets.

7) What happens to invalid values or text labels?

If the ignore option stays enabled, invalid tokens are skipped and counted. If you disable it, calculation stops until every entry is numeric.

8) What does the PDF export include?

The PDF export captures the visible result panel, including headline metrics, summary statistics, frequency distribution, and cleaned sorted values for quick sharing or filing.