Quick answer: The average is the sum divided by the count: for 85, 90, 78, 92 and 88 the sum is 433, so the average is 433 ÷ 5 = 86.6.
How it's calculated
Mean = (x₁ + x₂ + … + xₙ) ÷ n: add all the values and divide by how many there are.
A weighted average multiplies each value by its weight first: mean = Σ(w·x) ÷ Σw. Course grades by credit hours are a common example.
The mean is pulled by very large or small values. For skewed data, also look at the median in the mean, median and mode calculator.
Worked examples
- 85, 90, 78, 92, 88: 433 ÷ 5 = 86.6
- Weighted, weights 3, 3, 2, 4, 3: (255 + 270 + 156 + 368 + 264) ÷ 15 = 1,313 ÷ 15 = 87.53
- 2, 4, 9: 15 ÷ 3 = 5
Frequently asked questions
Is average the same as mean?
In everyday use, yes: "average" usually means the arithmetic mean. The median and mode are other kinds of average.
How do I calculate a GPA-style weighted average?
Choose Weighted, enter the grades as numbers and the credit hours as weights in the same order.
Can I paste a column from a spreadsheet?
Yes. Numbers on separate lines, or separated by commas or spaces, all work. Arabic digits are accepted too.
What is the average of 85, 90, 78, 92 and 88?
86.6. They add up to 433, and 433 divided by 5 is 86.6.
Does a zero count in the average?
Yes, and it'll pull the average down. Only leave something out if there's genuinely no value, like a test you didn't sit.
What is a moving average?
The average of the last few values, worked out again each time a new one comes in. It smooths out the daily ups and downs in things like prices or step counts.