Statistics Calculator with Quartiles, SD and Outliers
Paste a numeric dataset and receive a complete descriptive summary rather than only a mean and standard deviation. The calculator reports both sample and population measures, transparent quartile rules, skewness, median absolute deviation, outlier fences and a live distribution view.
Dataset and calculation choices
Descriptive statistics results
Descriptive statistics calculation guide
This statistics calculator provides a dedicated calculation workflow rather than a generic converter. Statistics depend on whether the entered numbers represent a complete population or a sample from a larger population. This calculator reports both versions rather than silently choosing one.
Center and spread
Mean uses the sum divided by count, median uses the central ordered value, and mode lists the most frequent values. Range, interquartile range, variance and standard deviation describe different aspects of spread.
Sample versus population standard deviation
Population variance divides by n. Sample variance divides by n − 1 to estimate population variability from a sample. Both are shown with their square-root standard deviations.
Quartile methods
Linear interpolation type 7 matches a common spreadsheet and statistical-software convention. Median-of-halves uses separate lower and upper subsets. The selected method is printed with the result.
Outliers and robust measures
Tukey fences use Q1 − k×IQR and Q3 + k×IQR. Median absolute deviation is a robust spread measure because a few extreme values have less influence than they have on variance.
Skewness and coefficient of variation
Adjusted Fisher–Pearson skewness summarizes asymmetry when at least three values are available. Coefficient of variation divides sample standard deviation by the absolute mean and is undefined when the mean is zero.
Should I use sample or population standard deviation?
Use population SD when the data are the entire population of interest; use sample SD when they are a sample used to estimate a larger population.
Why can quartiles differ between calculators?
Several accepted quartile definitions exist. This calculator names and lets you choose the method.
Can text or missing values be included?
No. Every token must be a valid finite number so omitted data are not silently misinterpreted.