# Outlier Calculator

Outliers make statistical analyses difficult. Here is a simple online outlier calculator which is used to find lower and upper class boundaries from the given set of numbers with ease.

## Find Lower and Upper Class Boundaries

Outliers make statistical analyses difficult. Here is a simple online outlier calculator which is used to find lower and upper class boundaries from the given set of numbers with ease.

Code to add this calci to your website

#### Formula:

Inter-quartile Range (IQR) = Q3 - Q1
Lower Outlier Boundary = Q1 - 1.5 x IQR
Upper Outlier Boundary = Q3 + 1.5 x IQR
**Where,**
Q1 = First Quartile
Q3 = Third Quartile
An outlier may be due to the difference in the measurement or it may indicate the experimental error, the latter is sometimes excluded from the dataset. An outlier can cause serious problems in statistical analyses. A set with an upper bound is said to be bounded from above by that bound, a set with a lower bound is said to be bounded from below by that bound. In the below online **outlier calculator**, just enter the list of numbers separated by a comma and click calculate to find lower and upper class boundaries (first, third quartiles, median, lower and upper boundaries) for the given list.

### Example

**Find the Inter-quartile by the number series of 1,2,5,3,11,9,10,15.**

First Quartile (Q1): 2.5

Median: 7

Third Quartile (Q3): 10.5

#### Inter-quartile Range

Inter-quartile Range (IQR) = Q3 - Q1

IQR = 10.5 - 2.5

IQR = 8

#### Lower Outlier Boundary

Lower Outlier Boundary = Q1 - 1.5 * IQR

LQB = 2.5 - 1.5 * 8

LQB = No boundaries at lower end

#### Upper Outlier Boundary

Upper Outlier Boundary = Q3 + 1.5 * IQR

UQB = 10.5 + 1.5 * 8

UQB = 22.5