Start with the assumptions
Each guide explains when its distribution fits and when another model is more appropriate.
Learn discrete probability by solving real examples
Choose a model, enter your values, and see the formula, assumptions, and interpretation together. StatSolver is a free browser-based study tool for students and curious problem-solvers.
A learning-first statistics resource
A calculator should show more than a number
Probability exercises are easier to check when the model, inputs, formula, and result are visible in one place. StatSolver combines interactive calculations with plain-language explanations so you can understand why a result is reasonable—not just copy it into an assignment.
Check a worked example
Use a concrete example to compare the formula, inputs, and interpretation before trying your own values.
Interpret the output
Read expected values, variance, cumulative probabilities, and limitations in context.
Explore Our Calculators
Joint Distribution
Compute marginal probabilities, covariance, correlation, and independence for two variables.
Binomial Distribution
Calculate probabilities for a fixed number of binary trials (Success/Failure).
Geometric Distribution
Determine the probability of needing k trials to achieve the first success.
Poisson Distribution
Model the number of events occurring within a fixed interval of time or space.
Bernoulli Distribution
The fundamental building block. Single trial with binary outcome.
Why StatSolver?
Transparent calculations
See the values and formula steps that lead to the result, including checks for invalid inputs.
Visual learning
Use probability tables, histograms, and summary statistics to connect formulas to outcomes.
Private by design
Calculator inputs run in your browser. Read the Privacy Policy for the data handled by hosting, analytics, and advertising services.
Understanding Discrete Probability
Unlike continuous distributions (like height or weight), discrete distributions deal with countable outcomes like the number of heads in a coin flip or the number of emails received in an hour.
StatSolver helps students and engineers model these scenarios using standard statistical models like the Bernoulli, Binomial, Poisson, Geometric, and Joint distributions. Each calculator includes input validation, an interactive result, and a distribution-specific guide explaining the model.
Not sure which model to use? Read our guide on Probability Distributions.
How the site is maintained
Clear scope, careful formulas, honest limitations
StatSolver is an educational aid, not a replacement for a textbook, instructor, or independent review of important results. Read how the calculators are designed, tested, and connected to reference material on the Methodology & accuracy page.