The Evaluate block

The Evaluate block is a powerful tool for manipulating and evaluating data. It’s ideal for filtering data, conditionally running parts of your flow, integrating complex logic, and validating data with tests.

Using TypeScript scripts or Flows Query Language (FQL) queries, you can set up the Evaluate block to process data and send the result. When using TypeScript, you can also define tests with the pm API (for example, pm.test()), and the block will output structured test results through a dedicated Tests port. The Evaluate block has pre-defined snippets to help you create FQL queries.

Input

variable - Accepts data from another block’s output port.

Output

• Result - Sends the result of the script or query.
• Tests - Sends an array of test results when pm.test() is used in a TypeScript script. Each result includes the test name, pass/fail status, error details (if any), index, and whether the test was skipped.

Setup

The Evaluate block processes data it receives from its input ports and inserted data blocks.

When created, the Evaluate block has one input port. When you connect another block to this port, the Evaluate block inserts a Select block and assigns the selected value to a variable named value1. To rename the variable, click it and enter a new name.

You can also change the inserted Select block to a different data block by clicking the Select block’s icon and choosing a data block from the dropdown list.

You can also insert more variable data blocks into the Evaluate block to process their data. For example, you could insert a String block into your Evaluate block, name the variable string1, and reference it in your query as string1. Click Add data blocks to insert a data block into your Evaluate block.

The Evaluate block has a text box where you can enter TypeScript to create scripts or FQL to create queries. Click the dropdown list at the top of the block to set the text box to use TypeScript or FQL. Then click inside the text box and enter your code. When using TypeScript, you can define tests with the pm API (for example, pm.test() and pm.expect()) directly in the script. Test results are displayed in the Tests tab and sent through the Tests output port when the block runs. When the text box is set to use FQL, you can click Snippets and choose from a list of common tasks.

Example

To see the Evaluate block in an example flow, check out Flow Snippets: Evaluate.

Related blocks

You can use the Condition and If blocks instead, depending on your use case.

You can insert the following blocks into the Evaluate block to process their data including the String, Bool, Number, Null, Select, Now, Date, Date & Time, List, Record, and Get Variable blocks.

Related pages

For tutorials that use the Evaluate block, see the following:

• Calculate the years since a milestone
• Create a count-based loop with the Repeat block
• Create a dashboard using Postman Flows
• Create a list-based loop with the For block
• Send information from one system to another using Postman Flows