Average Calculator

How to calculate average

The average—also called the arithmetic mean—is the sum of a set of numbers divided by how many numbers there are. Enter your numbers above, separated by commas, spaces, or line breaks, and the average calculator adds them up and divides by the count.

Average formula: Average = (x₁ + x₂ + … + xₙ) ÷ n

For example, to find the average of 2, 7, 19, 24, and 25, add them to get 77, then divide by the count of 5: 77 ÷ 5 = 15.4.

What the mean calculator shows

• The average (arithmetic mean), with the sum ÷ count step written out.
• The sum and count of the numbers.
• The median—the middle value after sorting, or the average of the two middle values when the count is even.
• The geometric mean—the nth root of the product of the numbers. It is not defined when that product is negative.
• The largest and smallest values and the range between them.
• A number line plotting every value with the mean and median marked, so you can see whether outliers pull the average away from the middle.

Mean, median, and geometric mean

The mean uses every value, so a single very large or very small number can shift it a lot. The median depends only on the middle of the sorted list, which makes it a better "typical value" for skewed data such as home prices or incomes. For 1, 2, 2, 3, and 100, the mean is 21.6 but the median is 2.

The geometric mean multiplies the numbers and takes the nth root. It suits values that grow by multiplication, such as yearly growth factors. For numbers that are zero or positive, it is always less than or equal to the arithmetic mean, and it is 0 if any value is 0.

Frequently asked questions

How do I find the mean?

To find the mean, add all the numbers together and divide the total by how many numbers you added. The mean of 4, 8, and 15 is (4 + 8 + 15) ÷ 3 = 27 ÷ 3 = 9.

How to find the average of numbers with decimals or negatives?

The method is the same. Negative numbers lower the sum, and decimals are added as usual. The average of −5, 2.5, and 1,000 is 997.5 ÷ 3 = 332.5.

Is the average the same as the mean?

In everyday use, yes—"average" usually means the arithmetic mean. Statisticians sometimes use "average" more loosely for any typical value, including the median or mode, so this calculator labels each one separately.

What is the difference between the mean and the median?

The mean is the sum divided by the count. The median is the middle value of the sorted list. When the data is symmetric they are close; when there are outliers, the median usually describes the typical value better.

Why does the geometric mean say "Not defined"?

The geometric mean is normally used for positive numbers. This calculator takes the nth root of the product: if any number is 0 the result is 0, and if the product is negative (an odd count of negative numbers) it shows "Not defined" rather than a value. Remove negative values or use the arithmetic mean instead.