Signed Call Web SDK

Learn how to integrate Signed Call Web SDK into your website and CRM portal.


CleverTap provides in-app calls via its Signed Call Web SDK, which means you can make and receive calls on any webpage or device with an internet connection and the Signed Call Web SDK. This document shows you how to integrate the Signed Call Web SDK and manage calls. To know more about the Signed Call feature, refer to Signed Call.

Permission Requirements

Following are the basic permission requirements for the Signed Call Web SDK:

  • Microphone (Required)
  • Notification (Optional but recommended)

Browser Requirements

Following are the basic browser requirements for the Signed Call Web SDK to work:

Browser NameVersion Number
Google ChromeV55 and above
Microsoft EdgeV15 and above
Mozilla FirefoxV43 and above
OperaV43 and above
SafariDoes not support

Integrate the CleverTap Web SDK

The Signed Call Web SDK uses CleverTap SDK for analytics. For that, Signed Call Web SDK requires an active CleverTap instance as a parameter during the SDK initialization. If the CleverTap instance is unavailable, the Signed Call Web SDK returns an error ERR_MISSING_INITPARAMETERS, and the Signed Call Web SDK does not initialize.

To integrate the CleverTap Web SDK, refer to the CleverTap Web SDK Integration Guide.


Minimum Supported Version

The Signed Call Web SDK integrates with CleverTap SDK v1.2.0 or higher.

Integrate Signed Call Web SDK

To integrate the Signed Call Web SDK, use the Node Package Manager (NPM). You can add the Signed Call Web SDK as an npm to your web app.

Use the following npm command to install the package:

npm install clevertap-signed-call

Import the installed package as follows:

import {initSignedCall} from 'clevertap-signed-call'

Initialize and Authenticate Signed Call Web SDK

Create a new instance of a SignedCallClient by calling the initSignedCall() function. This function returns a promise object whose then() and catch() can be utilized for the following scenarios:

Scenario 1: If the promise resolves successfully, the then() method receives SignedCallClient as a response, meaning that the Signed Call Web SDK is initialized successfully.

Scenario 2: If the promise is rejected, the catch() method receives an error, meaning that the Signed Call Web SDK initialization failed.

The syntax for initializing and authenticating the Signed Call Web SDK is as follows:

let SignedCallClient

    accountId: <string>,
    apikey: <string>,
    cuid: <string>,
    clevertap: <clevertap sdk instance>,
    name: <string / optional>,
    ringtone: <string / optional>
).then(client => SignedCallClient = client).catch(err => console.log(err))

The options parameter in the initSignedCall function expects a JSON object with the following properties:






  • Unique identity of the client's account.
  • Available from the CleverTap dashboard.




  • Unique identity of the client's account.
  • Available from the CleverTap dashboard.




Unique identity of the user.




The CleverTap Web SDK instance.




  • Name of the user.
  • The name must range between 3 and 25 characters.
ringtoneThe URL of the ringtone played on the caller's end during the outgoing call.
Note: The default ringtone plays without this parameter.


CUID Validation Rules

The following are the validation rules for cuid:

  • Must range between 5 and 50 characters.
  • Must start with either alphabet or number.
  • The name is case-sensitive, and only '_' is allowed as a special character.
  • The cuid parameter cannot be of type number-number, that is, a number followed by a special character, which is again followed by another number. For example, org_25 is allowed, but 91_8899555 is not permitted.
  • Must be unique for every user.
  • Must be unique for every device to allow multiple logins for the user from different devices. In such cases, the user will have multiple cuid's.

Make a Signed Call

The dialing screen displays when the SignedCallClient from the init() function invokes the call() method to make an outbound call.
This method returns a promise object whose then() and catch() can be utilized for the following scenarios:

Scenario 1: When the call is answered, the outgoing call screen transitions into the ongoing call screen. After the transition, the then() method receives an over status and indicates that the call is completed successfully.

Scenario 2: The declined and missed statuses received by the catch() method indicate that the receiver rejected the call (declined) or did not answer the call (missed).

The call() parameters are as follows:






It is the receiver's cuid. For example: receiver = β€œSome_Unique_ID”.




It specifies the context of the call. For example, Trainer is calling, Grocer is calling, Tutor is calling, and so on.




It is a JSON object with the following properties:

  • receiver_image (string): This URL displays the receiver's image on the outgoing call screen.
  • initiator_image (string): This URL displays the initiator's image on the incoming call screen.

Call Button Handling

Before initiating the call, verify whether the Signed Call services are enabled. Use the following isEnabled() method that returns Boolean data type:

if (SignedCallClient.isEnabled()) {, context, callOptions).then(response => {
  // if the call has been answered
  console.log("call status is: ",response)
  }).catch (err => {
   // if the call is either missed or declined 
  console.log("call status is: ", err)

Call Hangup Functionality

The hangup() function ends an ongoing call. The hangup functionality is user-driven, and ending the call depends on the user. For example, if one of the users in a call clicks the call hangup button from the ongoing call screen, the Signed Call Web SDK calls the hangup() function internally to end the call.

In the case of a metered call, when a business wants to end the call after a specific duration, it must maintain a timer in the app and call the SignedCallClient.hangup() function at the appropriate time.


Logout the Signed Call Web SDK

The logout function disables the Signed Call Web SDK's calling feature by calling the SignedCallClient.logout() method. After calling the logout() function, you must repeat the Initialization and Authentication steps to make a new call.


Manage Notification Permission

To receive a Signed Call notification from the web, you must enable both system-level and browser-level permissions. If any one of the permission is not enabled, you will not receive the signed call notification on the browser.

System-level Permissions

You can enable this permission from the Notification Center of your system. The following sections provide information about enabling permission from Macbook and Windows systems.


For Mac, toggle ON the Allow Notifications option from the Notifications Center to enable the notification for the required web browser, as shown in the following figure:


Enable Notification Permission for Google Chrome on Macbook


For Windows, toggle ON the Notifications option from the Notifications Settings to enable the notifications, as shown in the following figure:


Enable Notifications for Google Chrome on Windows

Browser-level Permissions

Whenever the Signed Web SDK is initialized, you are prompted to provide permission to receive the Signed Call notifications from the Web, as shown in the following figure. Click Allow to enable browser-level notification.


Allow Browser Level Permissions

The following is the sample Signed Call notification displayed on Google Chrome:


Sample Notification in Google Chrome


Notifications in Do Not Disturb (DND) Mode

If the user has enabled DND mode, the notification is sent directly to the Notification Center and rendered only in the notification tray.


The following example describes the implementation of Signed Call Web SDK Initialization, Make Call, Hangup Call (for metered connection), and Logout functions of the clevertap-signed-call via Node Package Manager (NPM):

import {initSignedCall} from 'clevertap-signed-call'

  //initiate the sdk
      accountId, //string, required
      apikey, // string, required
      cuid, // string,required
      clevertap, // clevertap instance, required
      name, // string, optional
      ringtone // string, optional
  }).then(client => SignedCallClient = client).catch(err => console.error(err))

  // make a call
  function call() {
    let callOptions = {
      receiver_image: "", // optional, string
      initiator_image: "" // optional, string

     * receiver {string, required}: cuid whom you are calling
     * context {reason, required}: reason of call
     * callOptions {optional}
     * */
    if (SignedCallClient.isEnabled()) {, context,calloptions)
      .then((response) => {
        console.log("Call response : ", response);
      .catch((error) => {
    } else {
      // wait for sdk to be enabled or re-initiate the sdk

    // Hangup a call automatically after 20000ms 
    setTimeout((SignedCallClient.hangup()), 20000)

    // Logout the sdk 
    let logout = function () {


The following table lists the different errors and their probable causes:

ERR_MISSING_INITPARAMETERSOne (or more) mandatory parameter is missing in SDK Initialization and Authentication.
ERR_INVALID_INITPARAMETERSParameters are not valid.
ERR_MISSING_CT_ACCOUNTIDSigned Call Web SDK is unable to find the Account ID associated with CleverTap.
ERR_MISSING_CT_IDSigned Call Web SDK cannot find the CleverTap ID.
ERR_INVALID_CREDENTIALSThe Account ID or API Key provided to the Signed Call is incorrect.
ERR_ALREADY_SIGNEDINThe cuid is currently connected to another device.
ERR_MIC_UNAVAILABLEMicrophone permission denied.
ERR_OUTGOING_CALL_IN_PROGRESSIf a call is already in progress, then another can only be initiated once the current call is over, missed, declined, or canceled.
ERR_INVALID_CALL_PARAMETERSThe parameters provided in Make Call are incorrect.
ERR_INTERNET_LOSTThe call did not occur successfully due to the loss of internet connection.
404The receiver's cuid is offline.


Q. Are Signed Call accountId and apikey the same as CleverTap's accountId and token?

A. No. Signed Call accountId and apikey differ from CleverTap's accountId and token. You can find these details under your dashboard's Signed Call Settings.

Q. How to resolve ERR_MISSING_CT_ID error even after passing the correct CleverTap instance to the clevertap-signed-call?

A. This error may occur if:

  • The CleverTap SDK's region and accountId parameters are incorrect.
  • CleverTap SDK is not initialized.

Ensure that these details are correct, and if this issue persists, raise an issue at CleverTap Support.

Q. Why is it recommended to enable the web browser notification permission for the business?

A. CleverTap recommends enabling web browser notification permission to avoid missing notifications in the following scenarios:

  • Use Case 1
    A user is actively working on the desktop but has minimized the browser. In this case, if the browser notification is not enabled, the user will find it difficult to land on the correct browser tab when receiving a call.

  • Use Case 2
    A user is actively working on a different browser tab. CleverTap highly recommends enabling the browser notification for the best web experience.