Statistics Calculators
Statistics calculators turn a list of numbers or a set of chances into a result such as a mean, a spread or a probability. Math Lantern has five of them, each showing every step of the working, so you can see how the answer was reached and check it yourself.
Pick a statistics calculator
Which calculator should I use?
| Calculator | Question it answers | You enter | You get |
|---|---|---|---|
| Z value table | How likely is a value below or above a z-score? | A z-score or an area | Areas under the standard normal curve |
| Standard deviation calculator | How spread out is my data? | A list of numbers | Standard deviation, variance, mean |
| Average calculator | What is the typical value, or my weighted grade? | A list of numbers, or scores with weights | Mean, median, mode, range, weighted average |
| Binomial distribution calculator | What is the chance of k successes in n trials? | n, p and k | Exact and cumulative probabilities |
| Probability calculator | What is the chance that two events both happen, or either happens? | Two probabilities and a number of repeats | And, or, not and repeat probabilities |
How the calculators relate
A typical sequence starts with the average of a data set, then measures its spread with the standard deviation, and then uses a z-score to place a single value on the normal curve. When the data counts successes in a fixed number of trials, the binomial distribution calculator gives the exact probabilities instead.
All five run in your browser, show the formula and the intermediate numbers, and round only the final display to six decimals.
Frequently asked questions
Do these calculators show the steps?
Yes. Each one lists the formula and the intermediate numbers so you can follow the working and check it by hand.
Which calculator is best for test scores?
Use the average calculator for the mean and for weighted grades, the standard deviation calculator for how spread out the scores are, and the z value table to compare one score with the class distribution.
Are the results exact?
They are computed in double-precision arithmetic in your browser and rounded to six decimals for display, which is far more precision than most coursework needs.
Is my data sent anywhere?
No. The numbers you type are used by the calculator in your browser and are not sent to the site.
For all tools, go back to the Factoring Calculator home page.
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