Tukuk-OS📈 Statistics Calculator
ℹ️ What this tool does & how it works
Descriptive statistics in one pass: every standard summary, and the two choices statistics pages usually hide are made explicit here — sample vs population standard deviation (÷ n−1 vs ÷ n, shown together) and the quartile method (linear interpolation, the type most software calls "inclusive"; different textbooks disagree at the third decimal, so the method is printed with the answer).
σ or s — the one choice you have to make
If your numbers are the whole population, the standard deviation divides the squared deviations by n. If they are a sample standing in for a bigger population, honest arithmetic divides by n−1 (Bessel's correction), because the sample mean was itself fitted to the data and swallowed one degree of freedom. This page shows both rather than guessing; for large n the two converge and the difference stops mattering.