Statistics Calculator
Enter a list of numbers (separated by commas or spaces) to calculate mean, median, mode, range, variance, and standard deviation.
How these statistics are calculated
Mean is the sum of all values divided by the count. Median is the middle value when the numbers are sorted (or the average of the two middle values for an even count). Mode is the most frequently occurring value — shown as — if every value appears equally often.
This calculator reports the sample standard deviation and sample variance (dividing by n−1 rather than n), which is the standard choice when your numbers are a sample from a larger population rather than the entire population itself.
Frequently asked questions
What's the difference between mean and median?
The mean is the arithmetic average; the median is the middle value. The median is less affected by extreme outliers, so it's often a better summary for skewed data.
What does standard deviation tell you?
Standard deviation measures how spread out the numbers are from the mean — a small standard deviation means the values are clustered close to the mean, a large one means they're spread out widely.
Why does my data set show no mode?
If every number in your list appears the same number of times (including each appearing just once), there's no single most-common value, so the mode is undefined.