Mean, median and mode — what's the difference?
All three describe the "centre" of a set of numbers, but in different ways. The mean is the average: add every value and divide by how many there are. The median is the middle value once the numbers are sorted — half fall below it and half above. The mode is simply the value that appears most often; a set can have one mode, several, or none at all.
When to use each
- Mean works well for evenly spread data, but a few very large or very small values can pull it off-centre.
- Median is more robust for skewed data like incomes or house prices, where outliers would distort the mean.
- Mode is the only one that works for categories or repeated readings — the most common shoe size, the most frequent rating.
Worked example
For the set 4, 8, 15, 16, 23, 42: the sum is 108 and the count is 6, so the mean is 18. Sorted, the two middle values are 15 and 16, so the median is 15.5. No value repeats, so there is no mode.
Frequently asked questions
Can a set of numbers have more than one mode?
Yes. If two or more values are tied for the highest frequency, the set is multimodal and this calculator lists all of them. If every value appears the same number of times, there is no mode.
What's the difference between mean and average?
In everyday use they're the same thing — "average" almost always means the arithmetic mean, which is what this calculator shows.
Does the calculator handle decimals and negative numbers?
Yes, both. You can mix whole numbers, decimals and negatives freely, separated by commas, spaces or new lines.
Is my data sent anywhere?
No. Everything runs in your browser — nothing you paste leaves your device.