An average calculator, in everyday language, almost always means the arithmetic mean: add the numbers, divide by how many there are. That is not the median (the middle value after sorting) and not the mode (the most common value). Those other averages answer other questions. This page computes the mean and says so in the result label.
You paste a list. Commas, spaces, semicolons, and line breaks all work as separators. Each token must be a number. If one token is “n/a” or “twelve,” the status names that token and the result stays hidden. Silent skipping would change the count and produce a mean that looks official and is wrong. That is the failure mode this average calculator is built to avoid.
The result shows count, sum, and average. Use it for a short homework list, a column copied from a sheet, or a set of measurements you do not want to retype into a spreadsheet. Related ideas live on the Ratio Calculator when you care about parts, and the Fraction Calculator when the numbers are fractions rather than a list of decimals.
The list box is a textarea, so Enter inserts a line instead of submitting. Use the Calculate button after a multi-line paste. Clear empties the box and hides the result.
average = sum ÷ count. Sum is the total of every accepted number, including negatives and zeros. Count is the number of accepted tokens. There is no weighting, no dropping of outliers, and no Winsorizing. If you need a weighted mean, this is the wrong page.
The list 12, 15, 18, 21 has count 4, sum 66, average 16.5. The list 10, x, 20 stops on “x”. The list with a trailing comma still averages the real numbers only, because empty tokens are not values. A single number 7 returns count 1, sum 7, average 7.
12 + 15 + 18 + 21 = 66
66 ÷ 4 = 16.5A common mistake is to average percentages that already have different bases, such as two class scores out of different totals, or two growth rates from different starting amounts. The mean of 10% and 50% is 30% as numbers, and that 30% may not describe either real quantity. Average the underlying amounts when that is the real question, then compute a percent if you still need one.
When the question is “how do these two parts compare,” use the Ratio Calculator. When the values are fractions you need to add first, use the Fraction Calculator, then average the decimals if that is still the right question. This page will not convert those fractions for you.
This is the arithmetic mean: sum divided by count. It is not the median or the mode.
The arithmetic mean only: sum divided by count. Median and mode are different jobs and are not calculated here.
Commas, semicolons, spaces, and new lines. Empty pieces are ignored; non-numeric pieces are errors.
The whole calculation stops and the status names the token. Nothing is averaged behind your back.
Yes. Count is 1, sum equals that number, and the average is the same number.