Standard Deviation Calculator
Calculate standard deviation, variance, mean, and other descriptive statistics f...Calculate standard deviation, variance, mean, and other descriptive statistics for any data set. Choose between population standard deviation (σ) and ...
Drop your PDF here
or click to browse (max 50MB)
Standard Deviation Features
Complete statistical analysis
Why Use Standard Deviation Calculator?
Complete Statistics
Get standard deviation, variance, mean, median, mode, range, sum, min, max, and count - all in one calculation.
Population & Sample
Choose between population standard deviation (when you have all data) or sample standard deviation (when working with a subset).
Step-by-Step
See the calculation steps and formula used, helping you understand how standard deviation is computed.
Instant Results
Enter your data and get results immediately. Handles large data sets with ease for quick analysis.
Common Use Cases
Statistics for every need
Statistics Homework
Check your statistics homework answers. Understand the calculation steps and verify your manual calculations are correct.
Data Analysis
Analyze variability in business data, research results, or survey responses. Understand how spread out your data is.
Scientific Research
Calculate measurement variability in experiments. Report standard deviation as error bars or uncertainty in your results.
Quality Control
Monitor process consistency in manufacturing or service delivery. Lower standard deviation means more consistent output.
How It Works
Enter Your Data
Type or paste your numbers separated by commas, spaces, or newlines. The calculator accepts any common format.
Choose Type
Select 'Sample' if your data is a subset of a larger population, or 'Population' if you have all possible values.
Set Precision
Choose how many decimal places you want in your results (2, 4, 6, or 8).
Get Statistics
Click calculate to see standard deviation, variance, mean, and other descriptive statistics for your data.
Pro Tips for Statistical Analysis
Watch for Outliers
Before interpreting standard deviation, check for outliers that might skew results. Consider removing extreme values or using median absolute deviation instead.
Use Coefficient of Variation
When comparing variability between data sets with different units or scales, use CV (std dev / mean × 100%) for meaningful comparison.
The 68-95-99.7 Rule
For normal distributions: ~68% of data falls within 1 std dev of the mean, ~95% within 2, and ~99.7% within 3 standard deviations.
Sample Size Matters
Larger samples give more reliable standard deviation estimates. With small samples (n < 30), be cautious about drawing conclusions.
Frequently Asked Questions
Trusted by Millions
“Super fast and easy to use!”
Sarah M.
“Best free PDF tool online”
John D.
“Saves me hours every week”
Mike R.
50M+
Files Processed
2M+
Happy Users
4.9
Star Rating
99.9%
Uptime