Average Calculator
Paste numbers to get the average (mean), sum and count.
How to use this calculator
Type or paste your numbers into the box separated by commas or spaces and press Calculate average. The tool returns the mean — the everyday average — along with the total and how many numbers you entered. It accepts decimals and negative values, so it works for grades, prices, measurements, ratings and any list you need the average of. Because it shows the sum and count too, you can quickly sanity-check the result by eye.
The formula explained
The average, or arithmetic mean, is simply the total shared equally across the items:
average = (sum of values) ÷ (number of values)
You add every number to get the sum, then divide by how many numbers there are. The result is the single value that, if every item were equal, would give the same total. This is why the average sits in the middle of the data and why a single very large or very small number can pull it noticeably in that direction.
A worked example
For 10, 20, 30 and 40: the sum is 100 and there are 4 numbers, so the average is 100 ÷ 4 = 25. Add a fifth number, 50, and the sum becomes 150 over 5 values, giving an average of 30 — each new value shifts the average toward itself.
Frequently asked questions
How do you calculate an average?
Add all the numbers and divide by how many there are.
Is the average the same as the mean?
Yes — the everyday average is the arithmetic mean.
Can I average decimals and negatives?
Yes — the calculator accepts both.