Standard Deviation Calculator

Calculate standard deviation and statistics

Data Input

Tips:

  • • Enter numbers separated by commas
  • • Decimals are supported
  • • Use sample mode for sample data
  • • Population mode for complete data

Results

1.5811
Standard Deviation

Basic Statistics:

Mean:3.0000
Median:3.0000
Mode:1, 2.0, 3.00, 4.000, 5.0000
Range:4.0000
Variance:2.5000

Advanced Statistics:

Skewness:0.0000
Kurtosis:-1.2000

Confidence Intervals:

68% Confidence Interval
1.4189 to 4.5811
95% Confidence Interval
-0.1623 to 6.1623
99% Confidence Interval
-1.7434 to 7.7434

Understanding Standard Deviation

What is Standard Deviation?

Standard deviation measures the amount of variation in a dataset. It indicates how far a set of numbers spreads out from their average value (mean).

  • • Small SD: Data clusters near the mean
  • • Large SD: Data spreads far from mean
  • • Units match original data
  • • Always non-negative

Sample vs Population

  • • Population: Complete dataset (n)
  • • Sample: Subset of population (n-1)
  • • Sample SD slightly larger
  • • Use sample for estimates

Applications

Science

  • • Experimental error
  • • Quality control
  • • Natural variation
  • • Measurement precision

Finance

  • • Investment risk
  • • Market volatility
  • • Portfolio analysis
  • • Performance metrics

Education

  • • Test score analysis
  • • Grade distribution
  • • Performance metrics
  • • Research analysis