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Standard Deviation Calculator

Paste your data. The math unfolds itself.

Standard deviation, variance, mean and a full step-by-step calculation for population or sample — pasted straight from a spreadsheet, stripped of blanks, and verified line by line.

Accepts spaces, commas, tabs or new lines. Blanks and invalid entries are ignored.

Results

Data points—
Mean—
Variance (σ²)—
Std deviation (σ)—
min — max — range —

Step-by-step working

The computation, laid out line by line so you can check every number. Calculate above to begin.

Quick spread analysis for any dataset

This calculator gives you the standard deviation of a set of numbers without requiring a spreadsheet or formula recall. Students use it to verify homework answers, researchers check summary statistics before running full analyses, and professionals measure variability in metrics like test scores, financial returns, or manufacturing tolerances. The tool handles both population and sample standard deviation, so you get the right divisor for your data whether you measured every member of a group or drew a representative subset.

Frequently Asked Questions

What is the difference between population and sample standard deviation?

Population standard deviation divides by N and describes a complete data set. Sample standard deviation divides by N−1 and estimates a wider population from a sample.

How do I enter my data?

Paste or type your numbers separated by commas, spaces or line breaks. The calculator cleans the input automatically before calculating.

Does it show the working?

Yes. The mean, variance and every squared deviation are shown step by step so you can follow the calculation.

Is the standard deviation calculator free?

It is free, needs no sign-up, and all computation happens locally in your browser.

Latest Articles

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