Standard Deviation Calculator
Compute mean, variance, and standard deviation from a list of numbers. Foundation for understanding variability in marketing metrics.
Entrées
Statistics
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Run calculation
Count—
Mean—
Variance—
Sample standard deviation—
Standard deviation tells you how much your data varies
A 5% conversion rate sounds great until you discover the standard deviation is 3% — meaning some weeks you hit 8% and others 2%. Marketing metrics with high variance need bigger samples to draw valid conclusions. Standard deviation is the tool for measuring that variance.
Foire aux questions
Sample or population?
The calculator uses the sample (n-1) formula, which is correct when your data is a sample of a larger population. Use it for analytics, surveys, and most marketing data.
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