This API is available on Firefox OS for internal applications only.

The MMICall interface of the Web Telephony API represents an MMI call, allowing us to receive the result of the call.

An MMICall is when you call a special number that contains MMI (Man-Machine Interface) codes (such as * or #.) Such a call can be initiated to perform specific functions on a phone (such as forwarding all calls to a specified number, checking phone credit balance, or displaying the phone's IMEI (Internatiol Mobile Equipment Identifier.)) You can find more details at What’s the difference between USSD, MMI and SS codes?


MMICall.result Read only
Returns a promise that resolves to an MozMMIResult object containing information associated with the success status of the MMI call.


// Telephony object
var tel = navigator.mozTelephony;

// Place a call
tel.dial("*123#").then(function(call) {
  call.result.then(function(MMIResult) {
    // do something with MMI result


Specification Status Comment
Web Telephony Draft Draft

Browser compatibility

For obvious reasons, support is primarily expected on mobile browsers.

Supported in Firefox OS 2.1.

See also

Document Tags and Contributors

 Contributors to this page: fscholz, chrisdavidmills, teoli
 Last updated by: fscholz,