Quick start
- Type your numbers separated by commas or spaces: 72, 85, 90, 64, 88.
- For a weighted average, type a weight for each number in the second box, in the same order.
- Read the average, the weighted average and the median.
How to find an average
Add all the numbers and divide by how many there are. For 72, 85, 90, 64 and 88: the sum is 399, there are 5 numbers, so the average is 399 ÷ 5 = 79.8.
Weighted average
When some values matter more, multiply each one by its weight, add the results, and divide by the total weight. A course where homework counts 20%, the midterm 30% and the final 50%, with scores of 80, 90 and 70:
(80 × 20 + 90 × 30 + 70 × 50) ÷ (20 + 30 + 50) = 7,800 ÷ 100 = 78.
The plain average of the three scores would be 80, which overstates the result because the lowest score has the biggest weight.
Average, median or mode?
The average (mean) uses every value, so one very large or small number can pull it a long way. The median, the middle value, is often better for things like salaries or house prices. Our guide on choosing an average explains when to use each.
Common questions
How do I calculate an average?
Add the numbers and divide by how many there are. The average of 4, 8 and 9 is 21 ÷ 3 = 7.
What is a weighted average?
An average where each value is multiplied by how much it counts before dividing by the total of the weights.
Do the weights have to add up to 100?
No. Any positive weights work, because the calculator divides by their total.
Can I paste numbers from a spreadsheet?
Yes. Commas, spaces and line breaks all work as separators.