Starlight Tools directory

Statistics & Probability Calculators

6 free, browser-based tools. No account required.

Free to use
Runs in your browser
No account required

Analyze datasets, calculate probabilities, explore distributions, and plan studies with private browser-based statistics tools. Start with the Mean, Median, Mode Calculator, Standard Deviation & Z-Score Calculator, or Binomial & Poisson Calculator.

Average (Mean) Calculator

Compute the arithmetic mean instantly, with the sum, count, minimum, maximum, range, and calculation steps. v1.0

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Mean, Median, Mode Calculator

Calculate the mean, median, mode, range, quartiles, and IQR for a set of numbers. v1.0

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Standard deviation and z-score calculator tool with data table and graph

Standard Deviation & Z-Score

Find the mean, variance, population or sample standard deviation, and per-value z-scores. v1.0

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Binomial and Poisson probability calculator tool with PMF and CDF chart

Binomial & Poisson Calculator

Calculate PMF, CDF, tail and range probabilities with expected value, variance, tables, and charts. v1.0

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Sample Size Calculator

Plan a two-sample t-test by solving for sample size, achieved power, or minimum detectable effect. v1.0

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Markov chain random walk tool with transition matrix and state graph

Markov Chain Calculator & Simulator

Analyze transition matrices, multi-step probabilities, stationary distributions, and simulated random walks. v1.0.0

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About These Statistics & Probability Calculators

These calculators cover descriptive statistics, probability distributions, study planning, and stochastic processes. Calculations run locally in your browser, and the tools show formulas, working, tables, or charts where useful.