How to use the average calculator
- Choose Mean, median and mode or Weighted average.
- Paste or type your numbers separated by commas, spaces or new lines.
- For a weighted average, enter one weight for each number in the same order.
- Read the mean, median, mode, range and other statistics. Download them as CSV if you want.
Formula
Mean = sum of values / count
Median = middle value of the sorted list (average of the two middle values if the count is even)
Mode = the value that appears most often
Weighted average = sum(value x weight) / sum(weights)
Sums are cleaned of tiny floating-point errors, so 0.1 + 0.2 shows as 0.3.
Worked example: six test scores
Scores: 88, 92, 79, 95, 88, 71. The sum is 513 and there are 6 scores, so the mean is 85.5.
Sorted: 71, 79, 88, 88, 92, 95. The two middle values are 88 and 88, so the median is 88. The value 88 appears twice, so the mode is 88. The range is 95 - 71 = 24.
Now treat the same scores as parts of a course with weights 20, 30, 10, 25, 10 and 5 percent. The weighted sum is 8,920 and the weights add up to 100, so the weighted average is 89.2.
Which average should I use?
The mean is affected by outliers. One very large value pulls it up. The median ignores them, which is why reports on housing prices and salaries often use it. The mode is useful for the most common value, such as a shoe size. Use a weighted average when some items count more than others, as in grades.
Typing a list quickly
You can paste a column from a spreadsheet directly into the box. Each line becomes a number. Currency signs, commas in numbers like 1,200 and percent signs are understood, so you do not need to clean the data first.
Assumptions and limits
- Entries that are not numbers are ignored, and the tool lists them.
- Up to 5,000 numbers are supported.
- Weights cannot be negative and must not add up to zero.
- If no value repeats, there is no mode.
Frequently asked questions
How do I find the average of numbers?
Add them up and divide by how many there are.
What is a weighted average?
An average where each value counts according to its weight. A final exam worth 40 percent affects the result more than a quiz worth 10 percent.
Can there be more than one mode?
Yes. If two values tie for most frequent, both are listed.