Average Calculator

An average calculator takes a list of numbers and returns the summary statistics that describe them, most importantly the mean, the median, and the mode. The mean is the arithmetic average, the sum of every value divided by how many values there are. The median is the middle value once the numbers are sorted, and the mode is the value that occurs most often. Reporting all three together matters because they answer different questions: the mean captures the overall level, the median resists being dragged around by a few extreme values, and the mode shows what is most common.

This tool goes past the three averages and computes the full picture in one pass. It gives you the count, the sum, the minimum and maximum, and the range between them, plus the variance and standard deviation in both their population and sample forms. Standard deviation tells you how spread out the numbers are around the mean, which is often more useful than the average alone: two data sets can share a mean of 50 while one clusters tightly and the other swings wildly, and only the standard deviation reveals the difference.

It also works as an average percentage calculator. Type the percentages as plain numbers without the % sign, because any entry that is not a number, such as 85%, is skipped: 82, 91, and 76 average to 83, which you read as 83%. A straight average of percentages is only correct when every percentage is out of the same total, like three tests each marked out of 100. If one test was out of 20 and another out of 200, add up the points and divide by the total possible instead, since this calculator gives every value equal weight.

You can paste numbers separated by commas, spaces, tabs, or new lines, so a copied spreadsheet column, a comma list, or space-separated figures all work without reformatting. Every calculation runs in your browser with JavaScript, so nothing you enter is uploaded, logged, or stored, and the tool keeps working offline once the page has loaded. It is built for quick checks in schoolwork, lab reports, finance, sports stats, and any situation where you need a set of numbers summarized correctly and instantly.