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Below you will find descriptions and links to 11 free statistics calculators for computing values associated with the normal distribution.

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This calculator will compute the 99%, 95%, and 90% confidence intervals for the mean of a normal population, given the sample mean, the sample size, and the sample standard deviation.

This calculator will compute the 99%, 95%, and 90% confidence intervals for the mean of a normal population when the population standard deviation is known, given the sample mean, the sample size, and the population standard deviation.

This calculator will tell you the cumulative area under the standard normal distribution, given a z-score (i.e., the cumulative probability from minus infinity to the z-score).

This calculator will compute the cumulative distribution function (CDF) for the normal distribution (i.e., the area under the normal distribution from negative infinity to x), given the upper limit of integration x, the mean, and the standard deviation.

This calculator will compute the cumulative distribution function (CDF) for the standard normal distribution (i.e., the area under the standard normal distribution from negative infinity to x), given the upper limit of integration x.

This calculator will tell you the one-tailed (right-tail) area under the standard normal curve, given a Z-score (i.e., the one-tailed probability from the z-score to positive infinity).

This calculator will compute the probability density function (PDF) for the normal distribution, given the mean, standard deviation, and the point at which to evaluate the function x.

This calculator will compute the probability density function (PDF) for the standard normal distribution, given the point at which to evaluate the function x.

This calculator will tell you the normal distribution Z-score associated with a given cumulative probability level.

This calculator will tell you the two-tailed area under the standard normal curve, given a Z-score (i.e., the two-tailed probability from +/- the Z-score to infinity on both tails of the distribution).

This calculator will compute a Z-score (i.e., a standard normal score), given an unstandardized raw value, the population mean, and the standard deviation of the population to which the unstandardized value belongs.