The Emarsys JavaScript API (also sometimes referred to as Web Extend) is a data collection system that captures the activity and behavior of website visitors. This information is used to enrich your Emarsys contact database with web behavior fields, and to generate personalized product recommendations for the Predict solutions.
Ready to jump in? Find our Javascipt API reference on the Emarsys Developer Hub.
How this works with other Emarsys products
The Emarsys JavaScript API may be used for both data collection and for obtaining Predict product recommendations. API features which are related to other Emarsys products (such as Predict) are marked as such in the Command Reference.
Prerequisites
In order to use the JavaScript API, you have to load the scarab-v2.js
JavaScript source to your page. The code snippet you need to insert into your websites HTML is available in your Emarsys Marketing Platform account. To display it, go to Admin > Data Sources and click Show tracking code in the Web Behavior box. The code you will see in the modal window already contains your Merchant ID, so all you need to do is paste it into your websites HTML.

Make sure to add our tracking code to all pages on your website, immediately before the </head>
element. As the scarab-v2.js
file is loaded asynchronously, it does not block the rendering of the page or the execution of other JavaScript code.
If you have already implemented the tracking code in your website, you can still display it at any time on the Data Sources page. To do so, find the Account Details box on the bottom right-hand side, and click Tracking code next to your Merchant ID.
Command Reference
You can find all information on implementing the Javascript API on your site on the Emarsys Developer Hub.
Web Extend supports the following commands: