Enter Your Data Set
Input your numbers separated by commas, spaces, or line breaks:
Calculation Results
Mean (Average): -
Sample Standard Deviation: -
Population Standard Deviation: -
Variance: -
Sum of Squares: -
Count: -
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Standard Deviation Calculator |
Standard Deviation Calculator: Measure Your Data Variability
Our Standard Deviation Calculator helps you measure the amount of variation or dispersion in your data set. Whether you're a student, researcher, or data analyst, this tool provides quick and accurate calculations of population standard deviation, sample standard deviation, variance, mean, and sum of squares.
Our Standard Deviation Calculator helps you measure the amount of variation or dispersion in your data set. Whether you're a student, researcher, or data analyst, this tool provides quick and accurate calculations of population standard deviation, sample standard deviation, variance, mean, and sum of squares.
Understanding Standard Deviation
Standard deviation is a statistical measure that quantifies 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.
Why Standard Deviation Matters
Standard deviation is crucial in fields like finance, research, and quality control because it:
- Measures investment risk in finance
- Helps determine the reliability of research results
- Identifies process variations in manufacturing
- Assesses climate variability in environmental science
Sample vs. Population Standard Deviation
Our calculator provides both sample and population standard deviation:
- Sample Standard Deviation: Used when your data represents a sample of a larger population
- Population Standard Deviation: Used when your data represents the entire population
Frequently Asked Questions
What is standard deviation used for?
Standard deviation is used to measure how spread out numbers are in a dataset. It's commonly used in finance to measure investment risk, in quality control to monitor process variations, and in research to assess data reliability.
When should I use sample standard deviation vs population standard deviation?
Use sample standard deviation when you're working with a subset of data from a larger population. Use population standard deviation when you have data for the entire population you're studying.
What does a high standard deviation indicate?
A high standard deviation indicates that data points are spread out over a wide range of values, suggesting greater variability in the dataset.
Can standard deviation be negative?
No, standard deviation cannot be negative because it's derived from squared differences and represents a measure of dispersion, which is always non-negative.
How is standard deviation calculated?
Standard deviation is calculated by:
- Finding the mean (average) of the dataset
- Calculating the squared difference of each value from the mean
- Averaging these squared differences
- Taking the square root of this average