Type or paste your numbers separated by commas or spaces. You'll get the mean (average) instantly, along with the median, sum, count, minimum, maximum, and range.
How the average calculator works
The average — formally the arithmetic mean — is the sum of your numbers divided by how many there are. It answers the question "if every value were the same, what would each one be?" This calculator also reports the median, minimum, maximum, sum, count, and range, because the mean alone can hide a lot: two data sets can share a mean of 18 while one is tightly clustered and the other is all over the place.
The formula
Mean = (x₁ + x₂ + … + xₙ) ÷ n
x₁ through xₙ are your values and n is how many there are. The median is the middle value once the list is sorted — or the mean of the two middle values when n is even.
Worked example
Take the numbers 4, 8, 15, 16, 23, 42:
Sum = 4 + 8 + 15 + 16 + 23 + 42 = 108, and there are 6 values, so the mean = 108 ÷ 6 = 18.
Sorted, the two middle values are 15 and 16, so the median = (15 + 16) ÷ 2 = 15.5. Min = 4, max = 42, range = 38.
When the mean lies to you
Notice in the example that the mean (18) is higher than the median (15.5). That's the fingerprint of a skewed data set: one large value (42) pulls the mean upward while the median stays put. As a rule of thumb, when mean and median disagree noticeably, report the median and mention the outliers — "average" household income, wait time, or test score can otherwise paint a picture that most of the actual data contradicts. The mean is the right tool when values genuinely pool together, like splitting a bill.
Frequently asked 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. For example, the average of 4, 8, 15, 16, 23, and 42 is 108 ÷ 6 = 18. This is technically called the arithmetic mean — the most common kind of average.
What's the difference between mean and median?
The mean is the sum divided by the count; the median is the middle value when the numbers are sorted (or the average of the two middle values if the count is even). The median ignores extreme values, so it's often more representative when the data has outliers.
When should I use the median instead of the mean?
Use the median when a few extreme values would distort the picture — incomes, house prices, response times. One billionaire in a room of a hundred people drags the mean income into the millions while the median barely moves. If mean and median are far apart, that gap itself is telling you the data is skewed.
How do I enter my numbers into this calculator?
Separate them with commas, spaces, or line breaks — any mix works, e.g. "4, 8 15,16". Decimals and negative numbers are fine. The calculator parses whatever you paste and tells you how many values it counted, so you can verify nothing was dropped.
What is the range of a data set?
The range is the maximum value minus the minimum value — a quick measure of how spread out the data is. For 4, 8, 15, 16, 23, 42 the range is 42 − 4 = 38. For a more nuanced spread measure, see the standard deviation calculator.