Send your event data from RudderStack to LaunchDarkly.

LaunchDarkly is a popular feature management platform that offers cutting-edge A/B testing and experimentation functionalities. It lets you efficiently automate and manage feature flags and improve overall product workflow and software quality.

RudderStack supports LaunchDarkly as a destination to which you can seamlessly send your data for flag management.

Getting started

RudderStack supports sending event data to LaunchDarkly via the following connection modes:

Connection ModeWebMobileServer
Device modeSupported--
Cloud mode---
In a web device mode integration, that is, using JavaScript SDK as a source, the LaunchDarkly native SDK is loaded from domain. Based on your website’s content security policy, you might need to allowlist this domain to load the LaunchDarkly SDK successfully.

Once you have confirmed that the source platform supports sending events to LaunchDarkly, follow these steps:

  1. From your RudderStack dashboard, add a source. Then, from the list of destinations, select LaunchDarkly.
  2. Assign a name to the destination and click Continue.

Connection settings

To successfully configure LaunchDarkly as a destination, you will need to configure the following settings:

LaunchDarkly connection settings
  • Client-side ID: Enter the client-side ID of your LaunchDarkly project.
For more information on getting the LaunchDarkly client-side ID, refer to the FAQ section below.


The identify call lets you create or update a user in LaunchDarkly.

You must call identify before making any track or alias calls.

A sample identify call is as shown below:

  "1hKOmRA4GRlm", {
    anonymous: false,
    avatar: "",
    country: "USA",
    custom: {
      favourite_color: "black"
    email: "",
    firstName: "Alex",
    ip: "",
    lastName: "Keener",
    name: "Alex Keener",
    privateAttributeNames: ["avatar", "country"],
    secondary: "abcd21234"

LaunchDarkly key

RudderStack assigns the userId to LaunchDarkly’s key field to uniquely identify a user.

key is the only required field in LaunchDarkly’s identify call. If no unique identifier is provided, RudderStack will automatically assign anonymousId as key.

Supported traits

The following table lists the supported fields for the traits object in the identify call:

anonymousBooleanOptionalMust be set to true.
avatarStringOptionalUser’s avatar image URL.
countryStringOptionalCountry associated with the user.
customObjectOptionalAdditional attributes associated with the user.
emailStringOptionalUser’s email address.
firstNameStringOptionalUser’s first name.
ipStringOptionalUser’s IP address.
lastNameStringOptionalUser’s last name.
nameStringOptionalUser’s full name.
privateAttributeNamesString ArrayOptionalList of attribute names (built-in or custom) marked as private and not sent to LaunchDarkly as analytics events.
secondaryStringOptionalUser’s secondary identifier.
If you have chosen to bucket the users by a specific attribute, the secondary field can be used to further distinguish the users who are otherwise identical as per that attribute.


The track call lets you record user events and send them to LaunchDarkly as custom conversion metrics for your experiments.

As mentioned above, you must call identify before sending any track events to LaunchDarkly.

A sample track call is as shown:

rudderanalytics.track("Test Event", {
  foo: "bar"


The alias call lets you merge different identities of a known user. You can explicitly change the identity of a user via this call.

A sample alias call is shown below:



Where do I get the LaunchDarkly Client-side ID?

To get your LaunchDarkly client-side ID, follow these steps:

  1. Log into your LaunchDarkly dashboard.
  2. Select your project:
LaunchDarkly projects
  1. Then, navigate to Account settings > Projects.
  2. You will see the client-side ID for your project here.
LaunchDarkly client-side ID

Questions? Contact us by email or on Slack