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Calculating Std Deviation

Standard Deviation Formula:

\[ SD = \sqrt{\frac{\sum(x_i - \text{Mean})^2}{n}} \]

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1. 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 the values tend to be close to the mean, while a high standard deviation indicates that the values are spread out over a wider range.

2. How Does the Calculator Work?

The calculator uses the standard deviation formula:

\[ SD = \sqrt{\frac{\sum(x_i - \text{Mean})^2}{n}} \]

Where:

Explanation: The formula calculates how much each data point differs from the mean, squares these differences, averages them, and takes the square root.

3. Importance of Standard Deviation

Details: Standard deviation is widely used in statistics to measure the spread of data. It's essential for understanding data variability, quality control, and risk assessment in various fields.

4. Using the Calculator

Tips: Enter your numerical data points separated by commas. The calculator will automatically filter out non-numeric values and compute the standard deviation.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between population and sample standard deviation?
A: Population SD divides by n, while sample SD divides by n-1 (Bessel's correction). This calculator computes population SD.

Q2: When should I use standard deviation?
A: Use it when you need to understand how spread out your data is from the mean, especially with normally distributed data.

Q3: What does a standard deviation of 0 mean?
A: A SD of 0 means all values in the dataset are identical (no variation).

Q4: How does standard deviation relate to variance?
A: Variance is the square of standard deviation. SD is in the same units as the original data, making it more interpretable.

Q5: Can standard deviation be negative?
A: No, standard deviation is always a non-negative value since it's derived from squared differences.

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