How to Use the Mean & Std Dev Calculator
This statistics calculator computes the most commonly used descriptive statistics from any list of numbers. Enter exam scores, temperatures, sales figures, or any numeric data to instantly get mean, median, variance, standard deviation, minimum, maximum, and range — all in one place.
Separate your numbers with commas or line breaks. Decimal numbers are supported. Choose Population mode (÷n) when your data represents the entire group, or Sample mode (÷n-1) when your data is a subset of a larger population. Sample mode provides an unbiased estimate of the true variance.
Standard deviation tells you how spread out the data is from the mean — a smaller value means data points are clustered near the mean. The median is resistant to outliers, making it a useful complement to the mean for skewed distributions. Range gives the simplest measure of spread by showing the difference between the largest and smallest values.
Frequently Asked Questions
Population standard deviation divides by n, while sample standard deviation divides by n-1. Use sample mode when you have collected part of a larger dataset to avoid underestimating the true variability.
Type or paste numbers separated by commas or line breaks. Example: 10, 20, 30, 40, 50. Decimal values such as 3.14 are also accepted.
The data is sorted in ascending order. For an odd count, the middle value is the median. For an even count, the median is the average of the two middle values.