Standard Deviation Calculator
Calculate the standard deviation for a set of numbers.
SAMPLE & POPULATION - PASTE DATA - RUNS ON YOUR DEVICE
Your data stays on your device
- n-1sample
- npopulation
- Pastenumbers
- Privateanalysis
What you can count on
- 0data sent
- Your number set is private
- Calculations are done locally
- 2formulas
- Choose sample (n-1)
- Or population (n)
- 100%on your device
- No server processing
- Results appear instantly
Standard Deviation Calculator at a glance
- What you enter
- Two or more; 1,234 counts as one
- Sample or population
- Sample (n−1) or population (n)
- What comes back
- Four headline figures and a table
- How many at once
- One set of numbers at a time
- Where it runs
- Numbers stay in your browser tab
- Extra figures
- 6 named figures alongside
- Price
- Free
- Account required
- No
How to use Standard Deviation Calculator
- 1
Enter Your Data
Paste your list of numbers into the text area. Enter numbers separated by supported delimiters such as spaces, commas, or line breaks.
- 2
Select Data Type
Choose whether your set of numbers represents a `Sample` from a larger population or the `Entire Population`. This choice affects the formula used.
- 3
View Your Results
The tool instantly calculates and displays the results. You will see the count of numbers, the mean (average), the variance, and the standard deviation.
Frequently asked questions
What is the difference between sample and population standard deviation?
Use 'population' when your data includes every member of a group (e.g., one classroom). Use 'sample' for a subset of a larger group (e.g., 100 students representing a country). The sample formula uses n-1 for a better estimate.
How should I format my numbers for the calculator?
Commas, spaces and new lines separate numbers. A comma inside a figure means thousands when the groups are exactly three, so 1,234 and 1,234.56 each count as one. European 1.234,56 works too. But 1,5 stays two numbers, because it is ambiguous.
Is there a limit to how many numbers I can enter?
The practical input limit depends on your browser, device memory, and dataset.
Are my calculations and data private?
Yes. All calculations are performed directly on your computer within your browser. Your data is never sent to, processed by, or stored on any external server. Your information remains entirely on your own device.
What do the other results like mean and variance represent?
The mean is the average of your numbers. Variance also measures spread; population variance divides by n, sample by n-1. Standard deviation is the square root of variance, returning the measure of spread to the data's original units.
Sample vs. Population
Paste a list of numbers and choose whether it represents a sample or an entire population. The tool instantly provides the mean, variance, and standard deviation.
- The choice between 'sample' and 'population' is critical for accuracy. Use 'population' if your data includes every member of the group you are studying.
- Use 'sample' if your data is a subset of a larger group. Its formula divides by n-1 to better estimate the whole population's variation.
Full specification
| What you enter | Numbers separated by commas, spaces or new lines. Two at the least. 1,234 reads as one number; 1,5 reads as two. |
|---|---|
| Sample or population | Choose Sample for n−1 or Population for n. The choice changes the formula. |
| What comes back | Standard deviation, variance, mean and count, with a table of six statistics. |
| How many at once | One set of numbers at a time. |
| Where it runs | The numbers stay in your browser tab and are gone when you close it. |
| Extra figures | Median, minimum, maximum, range, sum of squares and standard error come with the result, each named in its own row. |
| Price | Free |
| Account required | No |
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