# Tableau Calculated Field

**A calculated field allows you to do two major functions:**

- Create a New Field based on existing Measures and Dimensions
- Alter an Existing Field

**What is a calculated field in Tableau**

I think it’s only fitting to establish exactly what a field is. A field comprises the the dimension and metrics that are part of the data you have. These are all listed on the data pane to the left. A calculated field is a custom metric or dimension that you create using a calculation or rule. This can range from user, logical, type manipulation, aggregate function, number functions, and date functions. This is a very useful subject that will allow you to transform your data with built-functions.

**How to Create a Calculated Field**

**Option 1:**Right Click an empty space in the data pane and choose calculated field. At this point you can create a multitude of new fields to help you better understand your data. Open the window is open you will have a formula box and provide you with a list of functions that you can use to create your calculated field.**Open 2:**Right click a dimension or measure field and select a calculated field based on that element.**Option 3:**Drag the a field into the formula box

**Ten Common Formulas for Calculated Field**

1. **Case Function**

Case function is similar to an If statement. Case creates a conditions that must be met to return a result. Here is a simple example of a case formula.

CASE [Weekday] WHEN “Monday” THEN “Working” WHEN “Sunday” THEN “Not Working” ELSE “Closed” END

2.** IF Function**

IF is similar to Case. However, it allows you to mix different data types such as strings and integers.

IF [Profit]>[Cost] THEN “Profitable” ELSE “Not Profitable” END

3. **MAX **

This returns the maximum value in a data set.

MAX(1232, 3243,555,90,345) = 3243

4. **MIN **

This returns the minimum value in a data set.

MIN(1232, 3243,555,90,345) = 90

5.** DATEPARSE**

This function will convert a string into a date format of your specification.

DATEPARSE(mm.dd.yyyy, “29/July/2001”) = July-29-2001

6. **ADD/SUBTRACT/MULTIPLY**

7. **CONTAINS **

This is a string function that check whether a string elements exist in another string.

CONTAINS (“Absentdata”, “data”) = TRUE

8. **SUM/COUNT/AVERAGE**

9. **TRIM **

This function removes spaces around a string.

TRIM(” Biggy “) = “Biggy”

10. **MEDIAN**

Returns the middle number in a sequence of numbers

MEDIAN(13,44,66,90,134,200,250) =90