Probability calculator statistics with mean and standard deviation

Average Calculator

Calculate the average of a set of data. Average is the same as mean.
average = sum of data / number of data values

Basic Statistics Calculator

Calculate the minimum, maximum, sum, count, mean, median, mode, standard deviation and variance for a data set.

Descriptive Statistics Calculator

Calculations include the basic descriptive statistics plus additional values. Calculate the minimum, maximum, range, sum, count, mean, median, mode, standard deviation, variance, midrange, quartiles, sum of squares, mean deviation, absolute deviation, root mean square, standard error of the mean, skewness, kurtosis, coefficient of variation and frequency for a set of data.

Final Exam Grade Calculator

Calculate the grade you need on the final exam to get a desired grade for the course.

GPA Calculator

Calculate grade point average and cumulative grade point averages.

Mean Calculator

Calculate the mean of a set of data. Mean is the same as average.
mean = sum of data / number of data values

Mean Median Mode Calculator

Calculate the statistical mean, median and mode for a set of data.

Odds Probability

Convert "odds of winning" an event into a percentage chance of success.

Percentile Calculator

Calculate any percentile and get a table of every 5th percentile for a given data set.

Quartile Calculator

Calculate first, second and third quartiles, the interquartile range, and minimum and maximum for a data set.

Interquartile Range Calculator

Calculate first, second and third quartiles, the interquartile range, and minimum and maximum for a data set.

PIN Generator

Create PIN numbers of 1 to 100 digits long with or without repeats.

Random Card Generator

Draw 1 to 52 cards randomly from a shuffled deck of playing cards.

Random Name Picker

Randomly pick a name or multiple names from a list. Sort a list of names or generate multiple picks with repeats.

Random Number Generator

Generate one or more random numbers from a custom range of numbers you select with or without repeats and sorting.

Random Number Generator 1-10

Pick a randomly generated number between 1 and 10.

Random Number Generator 1-100

Pick a randomly generated number between 1 and 100.

Random Number and Letter Set Generator

Generate one or more random numbers or random letter sets from a range of numbers or letters.

Standard Deviation Calculator

Calculate the standard deviation and variance for a set of data.

Statistics Formulas

Formulas include the basic descriptive statistics to calculate the minimum, maximum, range, sum, count, mean, median, mode, standard deviation, variance, midrange, percentiles, quartiles, outliers, sum of squares, mean deviation, absolute deviation, root mean square, standard error of the mean, skewness, kurtosis, kurtosis excess, and coefficient of variation.

Stem and Leaf Plot Generator

Create stem and leaf plots, or stemplots, for sets of data values and calculate basic statistics including the minimum, maximum, sum, count, mean, median, mode, standard deviation and variance.

Sum Calculator

Calculate the sum of a set of numbers. Calculator performs addition or summation to compute the total amount of entered data set.

Variance Calculator

Calculate variance, standard deviation and variables needed to calculate variance including sample size n, mean and sum of squares of the sample set.

Vote Percentage Calculator

Calculate the percentage weight of two or three numbers that make up a total sum of the sample set.

Z-Score Calculator

Calculate the z-score using one of three methods including for a set of data.

Use this calculator to compute the z-score of a normal distribution.

Z-score and Probability Converter

Please provide any one value to convert between z-score and probability. This is the equivalent of referencing a z-table.

Probability between Two Z-scores

Use this calculator to find the probability (area P in the diagram) between two z-scores.

What is z-score?

The z-score, also referred to as standard score, z-value, and normal score, among other things, is a dimensionless quantity that is used to indicate the signed, fractional, number of standard deviations by which an event is above the mean value being measured. Values above the mean have positive z-scores, while values below the mean have negative z-scores.

The z-score can be calculated by subtracting the population mean from the raw score, or data point in question (a test score, height, age, etc.), then dividing the difference by the population standard deviation:

where x is the raw score, μ is the population mean, and σ is the population standard deviation.

The z-score has numerous applications and can be used to perform a z-test, calculate prediction intervals, process control applications, comparison of scores on different scales, and more.

Z-table

A z-table, also known as a standard normal table or unit normal table, is a table that consists of standardized values that are used to determine the probability that a given statistic is below, above, or between the standard normal distribution.

The table below is a right-tail z-table. Although there are a number of types of z-tables, the right-tail z-table is commonly what is meant when a z-table is referenced. It is used to find the area between z = 0 and any positive value, and reference the area to the right-hand side of the standard deviation curve.

Z Table from Mean (0 to Z)

How do you find probability with mean and standard deviation?

How do you find probability in statistics?