Average Calculator

About this tool

Paste or type a list of numbers and this calculator returns the average (mean), median, mode, range, sum, count, minimum and maximum together. It is handy for grades, survey results, prices or any data set. Everything runs in your browser and nothing you type is stored or sent.

How to use it

Enter numbers separated by commas, spaces or line breaks. Negative numbers and decimals are fine, and anything that is not a number is ignored. Results update as you type, so you can paste a column straight from a spreadsheet.

Mean, median and mode explained

• Mean (average): add all the numbers and divide by how many there are. For 12, 15, 15, 18, 22, 30 the sum is 112 and the mean is 18.67.
• Median: the middle value once the numbers are sorted. With an even count it is the mean of the two middle values, here (15 + 18) / 2 = 16.5.
• Mode: the value that appears most often. Here it is 15. A set can have several modes, or none if every value is unique.
• Range: the largest value minus the smallest, here 30 - 12 = 18.

Which one should you use?

The mean uses every value, so it is pulled by extreme numbers. The median ignores them, which is why household income and house prices are usually reported as medians. The mode suits categories and repeated values, such as the most common shoe size sold.

Worked example

Test scores of 70, 80, 90 and 100 have a sum of 340 and a mean of 85. Add one score of 10 and the sum is 350 over five scores, so the mean falls to 70, while the median is still 80. This shows how a single outlier moves the mean far more than the median.

Things to watch out for

An average of averages is not the average of the combined data unless each group is the same size, so average the raw values when you can. Weighted data, such as course grades with different credit values, needs a weighted average instead. Also check for typos and outliers before relying on the mean.