An advanced statistics calculator: paste one data set and get the interquartile range, skewness, kurtosis, mode, coefficient of variation, Shannon entropy, the T statistic and a Z score for every point - handy for checking a distribution, spotting extreme values or getting started with hypothesis testing.

Every definition is stated up front so results match other software:
   - Quartiles use linear interpolation (Excel QUARTILE.INC, position = (n-1) x p) and IQR = Q3 - Q1;
   - Skewness is the sample skewness (Excel SKEW, needs n >= 3);
   - Kurtosis is the excess kurtosis (Excel KURT, 0 for a normal distribution, needs n >= 4);
   - The mode is the most frequent value, ties are all listed, and a dash appears when no value repeats;
   - Coefficient of variation CV = s / mu;
   - Entropy is Shannon entropy over the frequency share of each distinct value, with a base of 2, e or 10;
   - Z scores are computed per data point as (x - mu) / s, and the T statistic is (mu - mu0) / (s / sqrt(n)) with mu0 taken from the parameter box.
Every sigma / s above is the sample standard deviation (divisor n-1). When there is not enough data or sigma = 0 the metric shows a dash instead of NaN or Infinity, and the Definition column of the table spells out each formula.

For basic metrics (mean / variance / standard deviation) use the Statistics Calculator on this site - this tool is deliberately limited to the advanced ones. Negatives and decimals are supported, values can be separated by commas, spaces or newlines, and results can be copied or exported as CSV.