This topic explains how to create a custom conversion binary metric in LaunchDarkly. Custom conversion binary metrics track how many contexts trigger an event. You can use this metric with any event you set up in your codebase.
For example, you can use custom conversion binary metrics to track:
SDKs send events at regular intervals, such as every five seconds. If a browser redirects an end user to another page, any events that occurred between when the SDK last sent events and when the browser redirected will be lost. To avoid this, call track and then flush when you know the browser will redirect an end user to another page, such as on click. To learn more, read Sending custom events and Flushing events.
When you create a custom conversion binary metric, you must first select Occurrence for what you want to measure.
Then, custom conversion binary metric definition options include:
To learn more about the metric definition options, read Metric components.
Custom conversion binary metrics require an event key from your application’s code to track conversions for any event in your code. To add a custom conversion binary metric in LaunchDarkly, you must identify it with a code snippet embedded in your app.
This is an example of sending a custom event:
The area of your code you should put custom conversion binary metric information into, and the type of information you should include, varies based on which SDKs you use. Often, the information you should put in your code includes the event key, context object, data field, or numeric value fields.
Sending custom events to LaunchDarkly requires a unique event key. You can set the event key to anything you want. Adding this event key to your codebase lets your SDK track actions customers take in your app as events. To learn more, read Sending custom events.
LaunchDarkly also automatically generates a metric key when you create a metric. You only use the metric key to identify the metric in API calls. To learn more, read Creating and managing metrics.
Try it in your SDK: Sending custom events
To create a custom conversion binary metric:

You can connect the metric to an experiment or guarded rollout to monitor the impact of a flag change.
You can also use the REST API: Create metric