Standard Deviation Calculator

What is Standard Deviation?

Standard deviation is a measure of the amount of variation or dispersion in a set of values. A low standard deviation indicates that values tend to be close to the mean, while a high standard deviation indicates that values are spread out over a wider range.

It's one of the most important measures in statistics, used to understand data distribution and assess risk in various fields including finance, science, and quality control.

Standard Deviation Formula

Interpreting Standard Deviation

• Low standard deviation: Data points are close to the mean (less variability)
• High standard deviation: Data points are spread out (more variability)
• In a normal distribution, about 68% of values fall within 1 standard deviation of the mean
• About 95% fall within 2 standard deviations
• About 99.7% fall within 3 standard deviations

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