M
MJJ Tools

Variance Calculator

Calculate variance, standard deviation, mean, median, and comprehensive statistical analysis with support for both sample and population data

Sample Datasets

Data Input

Sample data uses n-1 in variance calculation (Bessel's correction)

Supports comma, space, semicolon, or newline separated values

Understanding Variance

What is Variance?
Variance measures how spread out data points are from the mean. Higher variance means more spread.
Sample vs Population:
Sample variance uses (n-1) denominator for unbiased estimation. Population variance uses (n) denominator.
Standard Deviation:
Square root of variance, expressed in same units as original data for easier interpretation.
Coefficient of Variation:
Relative measure of variability (SD/mean × 100%) allowing comparison across different scales.

Applications & Uses

Quality Control:
Monitor process consistency and identify when variations exceed acceptable limits.
Risk Assessment:
In finance, variance measures investment risk and portfolio volatility.
Research & Analysis:
Compare variability between different groups, treatments, or experimental conditions.
Performance Evaluation:
Assess consistency in test scores, athletic performance, or business metrics.