Standard Deviation Calculator

Calculate the Standard Deviation, Variance, Mean, and Count for any data set. Supports both Population and Sample calculations.

Statistical Analysis

Data Set (separated by commas or spaces)

Data Type

Use Sample if your data is a subset of a larger group. Use Population if it represents the entire group.

How to Calculate Steps

Calculating Standard Deviation manually involves these steps:

Calculate the Mean (Average): Sum all numbers and divide by the count.
Calculate Deviations: Subtract the mean from each number.
Square the Deviations: Square each result from step 2.
Calculate Variance: Find the average of these squared numbers (divide by N for population, or N-1 for sample).
Find Standard Deviation: Take the square root of the Variance.

Standard deviation is widely used in finance (risk assessment), manufacturing (quality control), and scientific research to understand data consistency.