Standard Deviation Calculator

Free standard deviation calculator to measure data spread, calculate sample and population deviation, variance, Count, Mean and statistics instantly results.

Input Data
Deviation Type
Results :-
Standard Deviation (s) : 0.0000
Variance (s2) : 0.0000
Count (n) : 0
Mean (x̄) : 0.0000
Sum of Squares : 0.0000

What Is a Standard Deviation Calculator?

A Standard Deviation Calculator is a statistical tool used to measure how much values in a data set vary from the average (mean). It shows whether data points are closely grouped around the mean or widely spread out.

This calculator is commonly used in statistics, finance, research, and education to analyze data consistency and variability. By automating complex calculations, it saves time, reduces errors, and provides accurate results for better data interpretation and decision-making.

The Standard Deviation Formula

In mathematics and statistics, standard deviation measures how spread out the values in a data set are from the mean. The most commonly used formula for population standard deviation is σ = √[ Σ(x − μ)² ÷ N ], where x represents each data value, μ is the mean, and N is the total number of values.

For sample data, the formula is slightly different: s = √[ Σ(x − x̄)² ÷ (n − 1) ]. This adjustment improves accuracy when analyzing a subset of data. Standard deviation formulas are widely used in statistics, finance, science, and research to understand data variation, consistency, and reliability.