Derived properties: Add new event and user properties retroactively

In some cases, you may want to run analyses based on properties that were not sent to Amplitude, but can be derived from existing properties. Amplitude’s derived properties allow you to create new event and user properties retroactively, based on functions and operators that you can apply across multiple existing properties. These do not affect your raw data and will be computed on the fly.

For example, you may want to create a chart that group by whether an item added to a shopping cart is eligible for a discount.  In that case, you could create a derived property whose value is a boolean based on whether the price exceeds a certain amount.

NOTE: Derived properties is only available to enterprise customers and customers who have purchased the Govern add-on (formerly known as the Taxonomy add-on). 

Create a derived property

NOTE: You must be an Admin or Manager to create a derived property.

To create a derived property, follow these steps:

1. In Govern, navigate to Derived Properties tab.
2. Click Derive New Property at the top of the table.
3. In the Derive New Property modal, enter a new property name (required) and description (optional).
4. Enter your formula. See below for the list of valid functions and operators.
5. Click Save. Derived properties will be denoted in the Govern properties tables with the 𝑓𝑥 symbol.

Preview your results

As long as the formula you entered was valid, you can preview the results in the space below the formula editor. Do this by selecting existing values for properties used in the formula, or test out any free-form values. You can do this from either the Create/Edit modal, or from the side panel for a saved derived property.

Derived property use cases

Taking our previous referrer URL example, you can write a formula using string operators that looks like this:

SPLIT(referrer_url, "/", 2)

This formula will convert a value like "https://www.google.com/search?q=amplitude" into the value "www.google.com." But what if you want to strip this down even further, to just "google"? You can  do this by wrapping the result of a SPLIT function inside another SPLIT function. The resulting formula would look like this:

SPLIT(SPLIT(referrer_url, "/", 2), ".", 1)

Amplitude also supports math operators. Let’s say you have events that contain subtotal and tip properties, and you want to run some analyses based on the total amount. You can do this:

SUM(subtotal, tip)

Maybe you're also interested in knowing how many orders you would have given discounts to if the total order size was over $50. This formula will tell you whether a particular order would receive a discount:

IF(SUM(subtotal, tip) >= 50, true)

NOTE: Queries using derived properties may experience longer query times depending on the complexity of formulas. There is also a limit of up to 10 property references per derived property.

Using derived properties to calculate age

Many Amplitude customers want to calculate the ages of their customers. You can do this using derived properties:

1. Subtract the UNIX timestamp of the customer's date of birth from today's date in unixtime
2. Divide by the number of seconds in a year (31,536,000)
3. Round down

FLOOR( 
DIVIDE( 
MINUS( 
TODAY( 
), 
DATE_TO_LONG( 
birthday 
) 
), 
31536000000 
) 
)

Functions and operators

String functions

Math functions

Object functions

Date/ time functions

NOTE: Amplitude requires all Unix timestamps to be expressed in milliseconds.

Array functions

Conditional operators