Normal & Probability Distribution Calculator
Areas under the normal curve, the value for a given area, and binomial and Poisson probabilities. No z-table needed.
- CalculateNatural-display scientific calculator
- StatisticsMean, σ and s, quartiles, 7 regression models
- DistributionsNormal, inverse normal, binomial, Poisson
- EquationsSystems of 2–4 unknowns, quadratic to quartic, inequalities
- Matrix & vectorUp to 4×4: multiply, inverse, determinant; dot and cross
- Base-NBinary, octal, decimal, hex with and, or, xor
- Tablef(x) and g(x) for up to 200 rows, with a small chart
How to use
- Pick a distribution and a calculation at the top. Cumulative gives the probability of a range; density / probability gives the value at one point.
- For the normal distribution enter the mean μ and standard deviation σ. The standard normal has μ = 0 and σ = 1.
- Leave the lower bound empty for −∞ and the upper bound empty for +∞.
- Inverse normal finds the cut-off value from an area and its tail (left, right or center).
Example: with μ = 0 and σ = 1, P(−1.96 ≤ Z ≤ 1.96) ≈ 0.9500, and the inverse normal for a left area of 0.975 is about 1.959963985.
Other modes
- Statistics & regressionMean, σ and s, quartiles, 7 regression models
- Equation solverSystems of 2–4 unknowns, quadratic to quartic, inequalities
- Matrix & vectorUp to 4×4: multiply, inverse, determinant; dot and cross
- Base-NBinary, octal, decimal, hex with and, or, xor
- Table of valuesf(x) and g(x) for up to 200 rows, with a small chart
- CalculatorNatural-display scientific calculator