Mean, median and mode
Average Calculator: Mean, Median, Mode and Range
Paste a list of numbers to get the mean, median, mode, range, count, sum, minimum and maximum, with a note when an outlier pulls the mean away from the median.
The mean and the median are far apart, which usually means the data are skewed or include an outlier. The median is often the better summary in that case.
Every value is calculated in your browser from the standard normal distribution (Marsaglia’s series for Φ) and rounded to four decimals; the tables were checked cell by cell against an independent calculation. These tables give the area to the left of z. Some textbooks, including the NIST handbook, print the area from 0 to z instead, which is the left area minus 0.5 for positive z.
Mean, median or mode?
The mean adds every value and divides by the count; the median is the middle value once the numbers are sorted; the mode is the value that appears most often. In the example 12, 15, 15, 18, 20, 22, 95, the single value 95 pulls the mean up to 28.14 while the median stays at 18.
Common questions
What if there is no mode?
If every value appears once, there is no mode. If two or more values tie for the most appearances, each of them is a mode.
How is the median found for an even count?
Sort the numbers and average the two middle values. For 4, 7, 9 and 13 the median is (7 + 9) ÷ 2 = 8.
The studio notebook
A useful place to begin.
Clear steps, considered details, and ideas you can put to use.
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