What this calculator does
An average calculator answers the simplest and most common statistics question there is: given a list of numbers, what is the average? Type in the numbers, separated by commas or spaces, and the mean, sum and count come back immediately.
The average here is the arithmetic mean: add every number together, then divide by how many numbers there are. It is the same figure used for a class test average, an average of a set of expenses, or an average of any other list of measurements, and how to calculate average is exactly that one division.
The formula
Add up every number in the list, then divide that total by how many numbers are in the list. Ten numbers summing to 150 gives an average of 15, because 150 divided by 10 is 15.
| Term | Meaning |
|---|---|
| Average (mean) | The sum of all values divided by how many values there are. |
| Sum | The total of every number added together. |
| Count | How many numbers were entered. |
The inputs explained
| Field | What to enter |
|---|---|
| Numbers (comma or space separated) | A list of numbers, separated by commas, spaces or both. |
When to use it
Finding a class or test average
A set of test scores entered as a list gives the average score for the group in one step, the everyday case behind how to find the average that most people are looking for.
Averaging a set of measurements or bills
A run of monthly expenses, delivery times or measurements averaged together smooths out the noise in any single reading and gives a more representative figure.
Checking a reported average
Given the individual numbers behind a claimed average, this recalculates it directly, catching an error or a rounding difference in the original figure.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How does the average change as one more number is added to a fixed set?
A base set of three numbers (10, 20, 30, average 20), with one extra number added on top of it each time.
| Full list entered | Average (mean) | Sum of the numbers |
|---|---|---|
| 10, 20, 30, 0 | 15.000 | 60.000 |
| 10, 20, 30, 20 | 20.000 | 80.000 |
| 10, 20, 30, 40 | 25.000 | 100.000 |
| 10, 20, 30, 60 | 30.000 | 120.000 |
| 10, 20, 30, 100 | 40.000 | 160.000 |
| 10, 20, 30, 200 | 65.000 | 260.000 |
Questions
How do I calculate the average of a set of numbers?
Add all the numbers together, then divide by how many numbers there are. That single division is the whole calculation: no other steps are needed for a simple average.
How do I find the average of a large list quickly?
Paste or type the whole list into the calculator above, separated by commas or spaces, and the average, sum and count are worked out for the entire list at once.
Is the average the same as the median?
No. The average (mean) is the sum divided by the count. The median is the middle value once the numbers are sorted. A few very large or very small numbers pull the mean toward them but barely move the median, which is why the two can differ noticeably on skewed data.
Where can I get the median, mode and standard deviation as well?
This page is deliberately limited to the mean, sum and count. For the median, mode, standard deviation and quartiles from the same list, see the descriptive statistics calculator.
For median, mode, standard deviation and quartiles from the same data, see the descriptive statistics calculator. To average two values as a percentage change instead, see the percentage change calculator.