Sensors & Location

Magnetometer

Probing…

Magnetometer is a web platform capability in the Sensors & Location category. Magnetic field readings — a compass. available behind a flag in Chromium; not available in Firefox and Safari. Requires a secure context (HTTPS or localhost) and a user gesture such as a click or tap.

Secure contextUser gesture

Permission magnetometer: unknown

Try it

Loading demo…

Code

const sensor = new Magnetometer({ frequency: 10 })
sensor.addEventListener('reading', () => {
  // magnetic field in microtesla
  const heading = Math.atan2(sensor.y, sensor.x) * 180 / Math.PI
  console.log(sensor.x, sensor.y, sensor.z, heading)
})
sensor.addEventListener('error', e => console.warn(e.error))
sensor.start()

Browser support

Chromium
Behind a flag
Firefox
No
Safari
No

Frequently asked questions

Which browsers support Magnetometer?

available behind a flag in Chromium; not available in Firefox and Safari.

Does Magnetometer require HTTPS?

Yes. Magnetometer needs a secure context, so it only works over HTTPS (or on localhost during development).

What is Magnetometer used for?

Magnetic field readings — a compass.

Can I try Magnetometer in my browser?

Yes. shwcs.net runs a live Magnetometer demo that probes your current browser and lets you try the API. Everything runs locally — nothing is sent anywhere.

MDN reference ↗ Specification ↗