Mihsaba›Statistics & Probability

Statistics & Probability

Statistics and probability tools cover data summaries, distributions, confidence intervals and statistical tests with formulas and key assumptions.

Available calculators

Analyze data, probability, distributions, and statistical tests.

σ / s

Standard Deviation Calculator

Calculate mean, sum of squared deviations, variance and standard deviation for both population and sample from one data set.

Pₖ

Percentile Calculator

Find any percentile from a dataset using inclusive linear interpolation or nearest-rank, with Q1, median, Q3 and IQR.

Correlation Coefficient Calculator

Calculate Pearson’s r, r² and the simple regression line from paired data, with a reminder that correlation does not prove causation.

Confidence Interval Calculator

Calculate a confidence interval for a mean using Student’s t or for a proportion using the Wilson interval, with standard error, critical value and margin.

Sample Size Calculator

Calculate the minimum sample size for estimating a proportion or mean from confidence level and margin of error, with optional finite-population correction.

Normal Distribution Calculator

Calculate left-tail, right-tail and between-value probabilities for a normal distribution, or invert a percentile to an x value and z-score.

Standard Error Calculator

Calculate the standard error of a mean or proportion from sample inputs, with a clearly labeled approximate 95% normal-theory margin.

Bin(n,p)

Binomial Distribution Calculator

Calculate exact, at-most and at-least binomial probabilities for k successes in n independent trials with constant success probability p, plus mean, variance and standard deviation.

Pois(λ)

Poisson Distribution Calculator

Calculate exact, at-most and at-least Poisson probabilities from mean rate λ and integer count k, plus mean, variance and standard deviation.

CV%

Coefficient of Variation Calculator

Calculate coefficient of variation (CV) from a dataset with mean, standard deviation and variance, using sample or population formulas.

MAD

Mean Absolute Deviation Calculator

Calculate mean absolute deviation around the mean, median or a custom center, with mean, median and count shown alongside.

ŷ=a+bx

Linear Regression Calculator

Fit a simple least-squares regression line from X and Y values, including slope, intercept, correlation r, R² and an optional prediction.

Exp(λ)

Exponential Distribution Calculator

Calculate exponential PDF, CDF, survival and interval probabilities plus mean, variance and median from a positive rate λ.

P-Value Calculator

Calculate a p-value from a z, t or chi-square statistic, with tail selection, degrees of freedom and an optional significance-level comparison.

One-Sample T-Test Calculator

Calculate the t statistic, degrees of freedom and p-value for a one-sample t-test from sample mean, standard deviation, sample size and hypothesized mean.

χ²