Skip to content

node.js SDK for ConfigCat. ConfigCat is a hosted feature flag service: Manage feature toggles across frontend, backend, mobile, desktop apps. Alternative to LaunchDarkly. Management app + feature flag SDKs.



Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time

ConfigCat SDK for Node.js

ConfigCat SDK for Node.js provides easy integration for your application to ConfigCat.

ConfigCat is a feature flag and configuration management service that lets you separate releases from deployments. You can turn your features ON/OFF using ConfigCat Dashboard even after they are deployed. ConfigCat lets you target specific groups of users based on region, email or any other custom user attribute.

ConfigCat is a hosted feature flag service. Manage feature toggles across frontend, backend, mobile, desktop apps. Alternative to LaunchDarkly. Management app + feature flag SDKs.

Node CI codecov Known Vulnerabilities License Node.JS

Getting Started

1. Install and import package:

via NPM package:

npm i configcat-node
const configcat = require("configcat-node");

2. Go to the ConfigCat Dashboard to get your SDK Key:


3. Create a ConfigCat client instance:

const configCatClient = configcat.getClient("#YOUR-SDK-KEY#");

We strongly recommend using the ConfigCat Client as a Singleton object in your application.

4. Get your setting value:

The async/await way:

const value = await configCatClient.getValueAsync('isMyAwesomeFeatureEnabled', false);

if (value) {
} else {

or the Promise way:

configCatClient.getValueAsync('isMyAwesomeFeatureEnabled', false)
  .then((value) => {
    if (value) {
    } else {

Getting user specific setting values with Targeting

Using this feature, you will be able to get different setting values for different users in your application by passing a User Object to getValueAsync().

Read more about Targeting here.

const userObject = new configcat.User("#USER-IDENTIFIER#");
const value = await configCatClient.getValueAsync('isMyAwesomeFeatureEnabled', false, userObject);

if (value) {
} else {

Sample/Demo app

Polling Modes

The ConfigCat SDK supports 3 different polling mechanisms to acquire the setting values from ConfigCat. After latest setting values are downloaded, they are stored in the internal cache then all requests are served from there. Read more about Polling Modes and how to use them at ConfigCat Docs.

Need help?


Contributions are welcome. For more info please read the Contribution Guideline.

About ConfigCat


Make sure you have the proper Node.js version installed

You might run into errors caused by the wrong version of Node.js. To make sure you are using the recommended Node.js version follow these steps.

  1. Have nvm (Node Version Manager - ) installed:
  2. Run nvm install. This will install the compatible version of Node.js.
  3. Run nvm use. This will use the compatible version of Node.js.