Visualize request responses using Postman Visualizer

The Postman Visualizer provides a programmable way to visually represent your request responses. Visualization code added to the Tests for a request will render in the Visualize tab for the response body, alongside the Pretty, Raw, and Preview options.

Visualizer rendering

The Visualizer enables you to present your response data in ways that help to make sense of it. You can use this to model and highlight the information that's relevant to your project, instead of having to read through raw response data. When you share a Postman Collection, other people on your team can also understand your visualizations within the context of each request.

Visualizing response data

To visualize your response data, add code to the Pre-request or Tests script for the request. The pm.visualizer.set() method will apply your Visualizer code to the data and present it in the Visualize tab when the request runs.

Adding Visualizer code

The pm.visualizer.set() method accepts a Handlebars template string as its first parameter. The second parameter is the data you want to use the template to display. Read on to learn how you can build a Handlebars template and pass data to it.

Rendering HTML

For an example of the Visualizer in action, open the following collection in Postman:

Run in Postman

In the first request, the example endpoint responds with a list of names and email addresses with the following JSON response body structure:

        "name": "Alice",
        "email": ""
        "name": "Jack",
        "email": ""
    // ... and so on

The Visualizer code creates a Handlebars template to render a table displaying the names and email addresses by looping over an array. Handlebars can do this with the {{#each}} tag. This script runs in the request Tests:

var template = `
    <table bgcolor="#FFFFFF">

        {{#each response}}

The variable names inside the double curly braces in the template will be substituted by the data passed to the pm.visualizer.set() method. To apply the template, the following code completes the Tests script:

// Set visualizer
pm.visualizer.set(template, {
    // Pass the response body parsed as JSON as `data`
    response: pm.response.json()

The template variable is the template string created earlier. The second argument passed is an object defined as the response property—this is the variable that the template expects in the {{#each response}} loop. The value assigned to the response property is the response JSON data from the request parsed as an object.

Viewing visualizations

Send the request in Postman and select the Visualize tab. Postman renders the table as HTML, as it would be in a web browser.

Visualizer table rendering

Adding styling and interaction to visualizations

You can load an external stylesheet using <link> tags in your HTML template code, using the same technique as adding a stylesheet to a web page. You can also add stylesheets as <style> tags. Similarly, you can add interactions using JavaScript code in <script> tags inside your template HTML code.

Visualizer doesn't support interactions that download resources.

Using your own libraries

You can use any of the libraries in the Postman Sandbox to programmatically generate the layout template. To import another external JavaScript library, add the URL to a <script> tag in the template code, just as you would to load JavaScript into an HTML file. This lets you render your request data using the visualization tool of your choice (for example D3.js).

Accessing data inside the template

Any <script> elements inside your template can access the data passed in the second argument to pm.visualizer.set() by calling the pm.getData(callback) method. This is only applicable to JavaScript code in the template, for example if your template includes code to render a chart.

The pm.getData(callback) method takes a callback function as its parameter. This callback accepts two parameters: error and data. The second parameter is the data that was passed to pm.visualizer.set().

Using Postbot to create visualizations

Not sure how to write a visualization for your request? Ask Postbot! Tell Postbot what you want to do using plain language, and Postman uses artificial intelligence to generate a visualization for you. Use Postbot to create a new visualization, change the type of visualization, fix your existing visualization, and more.

To create a visualization with Postbot, do the following:

  1. Send your request so it has a response.
  2. In the Body tab of the response, select the Visualize tab.
  3. In the Visualize Response menu, select a table, chart, or graph visualizer. You can also select set up with a prompt and enter a text sentence to tell Postbot what you want to do using plain language. Postman uses artificial intelligence to generate a visualization for you.

For example, try these phrases with Postbot: "create a new visualization," "change the type of visualization," or "fix the existing visualization."

For more information on Postbot, visit About Postbot.

Try it out

For more examples of Visualizer code in action, add any of the following collections to your workspace by forking the collection. You can also export and then import the collection. After you fork or import the collection, open a request from Collections in the sidebar, then select Send. Postman will display the rendered data in the Visualize tab.

Collections icon You can see data visualizations in action in a sample collection template. To try out this template, select Data visualization.

Visualizer API

You can access the Visualizer from the Postman API. The pm.visualizer.set() method takes three parameters:

  • layout (required): The first parameter is a Handlebars HTML template string.
  • data (optional): The second parameter is data that you can bind to the template. The properties of this object can be accessed in the template.
  • options (optional): The third argument is an options object for Handlebars.compile(). You can use this to control how Handlebars compiles the template.

Postman uses the information you pass to pm.visualizer.set() to render an HTML page in the sandbox for the Visualizer. Select the Visualize tab for the rendered HTML page. The layout string is inserted into the <body> of the rendered page, including any JavaScript, CSS, and HTML that the template has.

Debugging the Visualizer

You can debug a visualization in Postman by right-clicking in the Visualize area and choosing Inspect visualization. This will open the Visualizer Developer Tools attached to the sandbox. You can use it in the same way as debugging a web page.

The Visualizer Developer Tools are only available in the Postman desktop app.

Debugging visualizers in Postman

Next steps

Now that you've learned about visualizing responses in Postman, you can start creating visualizations of your own.

  • To get started, you can experiment with the More Visualizer examples workspace. Run the example requests, then adjust the code to get the results you need for your own data.
  • For more information about how Postman provides access to your response data inside scripts, visit Postman test script examples.

Last modified: 2023/09/26