Average Calculator

The arithmetic mean tells you what each value would be if the total were shared equally across all entries. Enter numbers separated by commas to calculate their sum, the number of entries, and the mean. This works for examples such as test scores, daily measurements, or a set of prices when every entry should have equal weight.

The calculator treats each entered number as one observation. Repeated numbers count separately, which matters when you have a list such as 1, 2, 2, 3, 4, 5. To compare the mean with the median and most frequent value, use the Mean Median Mode Calculator. For spread around the mean, try the Standard Deviation Calculator.

How the mean uses sum and count

Add all values, then divide by the number of entries. For 4, 6, 10, and 12, the sum is 32 and the count is 4, so the mean is 8. The separate sum and count outputs make the answer easy to check. A repeated value counts again because it is a separate item in the list.

When the average can mislead

The mean is affected by unusually large or small values. For the list 10, 12, 13, and 65, the mean is 25 even though three values are near 12. If you want to describe a typical value in skewed data, compare the median rather than relying on the mean alone. This calculator does not compute weighted averages, medians, modes, or standard deviation.

Worked example

For 1, 2, 2, 3, 4, 5 the sum is 17 and n = 6, so the mean is 17/6 ≈ 2.833. That is the arithmetic mean, not the median (2.5) or the mode (2).

\[ \bar{x}=17/6\approx 2.833 \]

Frequently asked questions

Sources

• https://en.wikipedia.org/wiki/Arithmetic_mean

Assumptions and limitations

Enter at least one valid number; the tool uses equal weight for every listed entry. It reports the arithmetic mean, sum, and count, not the median, mode, weighted mean, or a measure of variability. Displayed precision can be rounded.