How to Add the Nexmo Client SDK to your JavaScript App

This tutorial shows you how to add the Nexmo Client SDK to your client-side JavaScript app.


The Nexmo Client SDK requires Node.js and npm.

To add the Nexmo Client SDK to your project

Open your terminal. If you have an existing app, navigate to its root. Otherwise, create a new directory for your project and add a default package.json by running:

npm init -y

Install the Client SDK package

Install the Nexmo Client SDK from npm:

npm install nexmo-client -s

Import the Client SDK into your code

If your app is using ES6 module syntax, you can import the client module near the top of your application code:

import ConversationClient from 'nexmo-client';

If your application will run on a single page, you can load the module in your HTML using a script tag:

<script src="./node_modules/nexmo-client/dist/conversationClient.js"></script>

Be sure to check that the path to conversationClient.js is correct for your project structure.

Using the Nexmo Client SDK in your app

Creating Users and JWTs

A JSON Web Token (JWT) is necessary to log in to your Nexmo Application. The Client SDK cannot manage users nor generate JWTs, so you must choose a method of handling it on the backend:

  • For onboarding or testing purposes, you can get your client-side app working before setting up a backend by generating a test JWT from the command line and hard-coding it in your client-side JavaScript.
  • For real world usage, you can deliver JWTs from the server using the Node or PHP backend SDKs, and set the jwt variable in your code by fetching that data:

      .then(results => results.json())
      .then(data => {
        jwt = data.token;
      .catch(err => console.log(err));
  • Read more on generating JWTs in this article

Instantiate and log in the ConversationClient

No arguments are necessary to instantiate a new ConversationClient, but you will need to pass your JWT as the argument to login().

let nexmo = new ConversationClient()
  .then(app => console.log('Logged in to app', app))
  .catch(err => console.log(err));


You added the Nexmo Client SDK to your client-side JavaScript app and logged in to a ConversationClient instance, which returned an Application object. You can now use Application.newConversation() to create a conversation, and then access the functionality of a Conversation.