RTCError

Baseline 2026
Newly available

Since April 2026, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The RTCError interface of the WebRTC API describes an error which has occurred while handling RTC operations. It's based upon the standard DOMException interface that describes general DOM errors.

DOMException RTCError

Constructor

RTCError()

Creates and returns a new RTCError object initialized with the different parameters and, optionally, a string to use as the value of the error's message property.

Instance properties

Also inherits properties from its parent interface, DOMException

errorDetail Read only

A string specifying the WebRTC-specific error code identifying the type of error that occurred.

receivedAlert Read only

A positive integer value indicating the fatal DTLS error which was received from the network. Only valid if the errorDetail string is dtls-failure. If null, no DTLS error was received.

sctpCauseCode Read only

An integer specifying the SCTP cause code indicating the cause of the failed SCTP negotiation. Set if errorDetail is sctp-failure. null if the error isn't an SCTP error.

sdpLineNumber Read only

An integer identifying the line number of the SDP on which the syntax error occurred. Set if errorDetail is sdp-syntax-error. null if the error isn't an SDP syntax error.

sentAlert Read only

A positive integer indicating the fatal DTLS error that was sent out by this device. Set if errorDetail is dtls-failure. If null, no DTLS error was transmitted.

Note: All RTCError objects have their name set to OperationError.

Examples

Basic usage

In this example, a handler is established for an RTCDataChannel's error event.

js
dataChannel.addEventListener("error", (event) => {
  let error = event.error; // event.error is an RTCError

  if (error.errorDetail === "sdp-syntax-error") {
    let errLine = error.sdpLineNumber;
    let errMessage = error.message;

    let alertMessage = `A syntax error occurred interpreting line ${errLine} of the SDP: ${errMessage}`;
    showMyAlertMessage("Data Channel Error", alertMessage);
  } else {
    terminateMyConnection();
  }
});

If the error is an SDP syntax error—indicated by its errorDetail property being sdp-syntax-error—, a message string is constructed to present the error message and the line number within the SDP at which the error occurred. This message is then displayed using a function called showMyAlertMessage(), which stands in for whatever output mechanism this code might use.

Any other error is treated as terminal, causing a terminateMyConnection() function to be called.

The above example uses addEventListener() to add the handler for error events. You can also use the RTCDataChannel object's onerror event handler property, like this:

js
dataChannel.onerror = (event) => {
  let error = event.error;

  /* and so forth */
};

Specifications

Specification
WebRTC: Real-Time Communication in Browsers
# dom-rtcerror

Browser compatibility