Unlock the Power of Klaviyo’s Public API with This Game-Changing Chrome Extension

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By Ben Timlons

The Integration: Klaviyo’s Public API inside a Chrome Extension

E-commerce developers, get ready to master yet another tutorial to add to your toolkit. This is a full guide to creating a Chrome extension using Klaviyo’s Public API, replicating the power of a guest post shared on Klaviyo’s blog.

Bottom Line: As an e-commerce business owner, you need to optimize your user experience, improve efficiency, and implement creative solutions. This tutorial unlocks opportunities to achieve all of these goals using Klaviyo’s Public API in a Chrome extension.

Future Predictions: The increasing push for browser-based solutions is clear, and the time is ripe to harness Klaviyo’s powerful API in diversely creative ways. We can predict a future where browser extensions with integrated APIS become standard, reducing the switch between multiple tabs and apps.

Beginning with the Basics for a Chrome Extension

Klaviyo’s Public API perfectly combines with any fetch request, expanding the capacity and accessibility of the CRM platform. The example used in this guide focuses on creating a basic Chrome extension that displays your Klaviyo account lists without web app login. This addition unfolds the potential to view your account details while keeping any tab open, instead of always returning to the Klaviyo site.

Prerequisites to Build a Chrome Extension

Make sure to have the following files for those with prior knowledge of building a Chrome extension:

  • Manifest.json file – Mandatory for a Chrome extension.
  • Background.js – Helps bypass service errors.
  • Style.css – Styles the front-end extension.
  • Popup.js – Implements the API Call.
  • Index.html – Displays the front-end of the extension.

This GitHub starter repository should assist those who prefer not to start from scratch and those seeking full file structure download.

Integrating Klaviyo’s Public API

The next part comprises the integration of Klaviyo’s Public API into your Chrome extension. To achieve this, utilize the popup.js file in a code editor and access Klaviyo’s full API References.

For this scenario, a Get List Call from Klaviyo’s API references is used. The aim is to grab the List Names from the API Call and directly display them in the extension interface.

This Loom video offers detailed instructions on completing this step.

Display List Names in Chrome Extension

After adding your API call to the popup.js file, the subsequent step is to execute a basic for loop to go through the list names in the response. This will populate the index.html div with the id of ‘finder’. The result is a Chrome extension populated with list names found in your Klaviyo account. Open the extension to view the List Names in your Chrome Browser.

If you need the final solution or want to compare your progress throughout the process, inspect this GitHub repository to find the complete solution.


With this tutorial, we’ve seen the extensive potential of integrating Klaviyo’s Public API in a Chrome extension. Leveraging this solution recipe will help extend Klaviyo beyond a standard web application interface, opening new prospects for custom solutions that are easily accessible and user-friendly. The direct interaction with Klaviyo offered by the Chrome extension bridges the gap between your browser and the Klaviyo platform, putting important data conveniently at your fingertips.

Moreover, the versatility of Klaviyo’s Public API supports the use of this solution recipe in a multitude of ways, limited only by your initiative and skill. The convenience of creating, managing, and viewing your email lists from the Chrome extension not only saves time, but also simplifies tasks that were once completely dependent on visiting the Klaviyo web app.