LaunchDarkly sample JavaScript application


We've built a simple browser application that demonstrates how LaunchDarkly's SDK works.


Below, you'll find the basic build procedure, but for more comprehensive instructions, you can visit your Quickstart page or the JavaScript SDK reference guide.

Build instructions


1. Edit index.html and set the value of clientSideID to your LaunchDarkly client-side ID. If there is an existing boolean feature flag in your LaunchDarkly project that you want to evaluate, set flagKey to the flag key.

const clientSideID = 'myClientSideID';
const flagKey = 'my-flag-key';

2. Open index.html in your browser.

You should receive the message "The feature flag evaluates to ." The application will run continuously and react to the flag changes in LaunchDarkly.