"Average" is three different questions wearing one word. The mean asks where the balance point is, the median asks what's typical, and the mode asks what's common — and on messy real-world data they can disagree loudly.
Mean: the balance point
Sum everything, divide by the count. The mean of 12, 15, 9, 22, 15, 18 is 91 ÷ 6 ≈ 15.17. It uses every value, which is its power and its weakness: a single extreme drags it hard. That sensitivity is why "average income" statistics can mislead.
Median: the outlier-proof middle
Sort the list and take the center (or the mean of the two center values). Add a billionaire to a room of nine ordinary earners: the mean income jumps by nine figures; the median barely blinks. The calculator flags when your mean and median diverge by more than 10% — the signature of skewed data, where the median is usually the honest summary.
Mode and range: quick texture
The mode is the crowd favorite — 15 in the example above, appearing twice. Lists can be multimodal or have no mode at all. Range (max − min) sketches the spread in one subtraction; for spread that weighs every point, graduate to the standard deviation calculator.
Paste-anything input
Numbers can arrive comma-, space-, semicolon- or newline-separated — straight from a spreadsheet column. Anything unparseable is counted and named, never silently dropped, so a stray header word can't quietly corrupt your average. Weighted averages, where values matter unequally, live in the weighted grade calculator.
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