JavaScript Navigator audioSession Property

What You’ll Learn

navigator.audioSession returns the document’s AudioSession object. Set type to tell the platform whether you are playing music, showing a short sound, or running a call. Learn feature detection, common types, five examples, and try-it labs.

Introduction

Phones and desktops constantly mix sounds: music, maps, notifications, and video calls. The Audio Session API lets a web page declare the kind of audio it produces so the OS can pause, duck, or mix other audio appropriately.

Your entry point is navigator.audioSession. That property is read-only and returns an AudioSession object. You usually set navigator.audioSession.type before starting playback or a call.

Understanding the audioSession Property

Think of audioSession as a handle to policy settings for this document’s audio. The most important setting today is type.

• navigator.audioSession is read-only and returns an AudioSession.
• AudioSession.type is readable and writable when the API exists.
• Types describe intent: playback, transient sounds, ambient mix, or play-and-record.
• Always feature-detect — the API is experimental and not Baseline.

📝 Syntax

General form of the property:

navigator.audioSession

Value

• An AudioSession object for the current document.

Common type values (MDN)

• "auto" — default; user agent chooses.
• "playback" — music / video / podcasts (often exclusive vs other playback).
• "transient" — short sounds; may duck other audio.
• "transient-solo" — exclusive prompts (for example directions).
• "ambient" — mixes with other audio.
• "play-and-record" — calls / mic + playback.

Common patterns

if ("audioSession" in navigator) {
  navigator.audioSession.type = "play-and-record";
}

// Then start media / getUserMedia as usual
const stream = await navigator.mediaDevices.getUserMedia({
  audio: true,
  video: true
});

Examples Gallery

Examples follow MDN Navigator.audioSession patterns with safe feature detection. Use View Output or Try It Yourself for each case.

const supported = "audioSession" in navigator;
console.log(supported ? "audioSession available" : "audioSession missing");

audioSession missing
(or "available" on a supporting browser)

if (!("audioSession" in navigator)) {
  console.log("audioSession not supported");
} else {
  console.log("type: " + navigator.audioSession.type);
}

audioSession not supported
(or "type: auto" when available)

function preparePlayback() {
  if ("audioSession" in navigator) {
    navigator.audioSession.type = "playback";
    return "set type=playback";
  }
  return "skipped (no audioSession)";
}

console.log(preparePlayback());
// Then: audioElement.play()

skipped (no audioSession)
(or "set type=playback")

async function startCallPreview() {
  if ("audioSession" in navigator) {
    navigator.audioSession.type = "play-and-record";
  }
  // Demo only logs intent — real apps call getUserMedia next
  return "ready for getUserMedia (audio+video)";
}

startCallPreview().then(console.log);

ready for getUserMedia (audio+video)

function setAudioSessionType(type) {
  if (!("audioSession" in navigator)) {
    return { ok: false, reason: "unsupported" };
  }
  navigator.audioSession.type = type;
  return { ok: true, type: navigator.audioSession.type };
}

const result = setAudioSessionType("transient");
console.log(JSON.stringify(result));
// {"ok":false,"reason":"unsupported"}
// or {"ok":true,"type":"transient"}

{"ok":false,"reason":"unsupported"}
(or {"ok":true,"type":"transient"})

🚀 Common Use Cases

• Music / video players — "playback" before play().
• Notifications — "transient" for short UI sounds.
• Navigation prompts — "transient-solo" for exclusive voice guidance.
• Video conferencing — "play-and-record" with mic + remote audio.
• Ambient / mix experiences — "ambient" when mixing is desired.
• Progressive enhancement — set type only when the API exists.

📝 Notes

• Experimental and not Baseline — support is limited.
• navigator.audioSession is read-only; configure via .type.
• Missing API is fine — media APIs still work without it.
• Set the type before starting the relevant media when possible.
• Related: appVersion, Window, JavaScript hub.

💡 Best Practices