This quartile calculator finds the first quartile (lower), second quartile (median) and third quartile (upper) of a data set and is designed for helping in statistics calculations. You can read more about it below the tool.
What is a quartile?
In statistics, a quartile is one of three points that divide a specific set of data into 4 equal groups, each group representing 1/4 part of the distributed sampled population.
The 3 types of quartiles are:
- first one (Q1) which is also called the lower quartile is equal to the data at the 25th percentile of the given set;
- second one (Q2) which is also known as the median;
- third one which is also referred to as upper quartile is equal to the data at the 75th percentile of the given set.
How does this quartile calculator work?
This quartile calculator uses McCabe's formula that does not take account of the median of the data set when computing the 1st and the 3rd quartiles.
Practically the 1st quartile is the median for the data set that contains all the values at the left of the 2nd quartile median, while the 3rd quartile is the median of the data set that contains all the values at the right of the 2nd quartile median.
As explained within instruction the number should be separated by commas, space or break line. For instance this data set: 1,2,3,4,5,6,7,8,9,10 and its results:
■ 1st quartile (lower quartile) = 3.25
■ 2st quartile (median) = 5.5
■ 3st quartile (upper quartile) = 7.7508 Apr, 2015