Compass
Phone compass with heading, direction and bearing lock, from your sensors.
About this tool
Open the page on a phone or tablet and tap Start compass. On iPhone and iPad, your browser asks for motion access first. Hold the device flat: the dial turns so the red needle points to magnetic north, and the large number shows the direction the top of the device is pointing, from 0° to 359°, with the compass direction. Lock bearing marks a direction on the dial and tells you which way to turn to stay on it.
How a phone compass works
Most phones and tablets contain a magnetometer, a sensor that measures the Earth's magnetic field in three dimensions. Combined with the accelerometer and gyroscope, it lets the device work out which way it's facing. Browsers expose this through the device orientation API, and on iOS through a dedicated compass heading. Headings are measured clockwise from north: 0° is north, 90° east, 180° south and 270° west, with in-between points such as north-east at 45°. To follow a bearing, lock it, then turn until the tool says you're on bearing. Magnetic north, which a compass points to, isn't quite the same as true north, the direction of the North Pole; the angle between them, called magnetic declination, depends on where you are and changes slowly over time, from near zero to several degrees in most populated places. Phones are easily disturbed by nearby magnets, including those in many phone cases and car mounts, steel structures, speakers and laptops. If readings jump, move the phone in a slow figure-of-eight to recalibrate. Honest limits: browser compasses are typically accurate to a few degrees at best. Laptops and desktops have no magnetometer, so they can't show a heading. Don't rely on a phone compass where navigation really matters; carry a proper compass and map. Sensor readings stay on your device. The distance between coordinates calculator gives bearings between places and the coordinate converter converts GPS formats.
Frequently asked questions
Why doesn't the compass work on my laptop?
Laptops and desktops don't have a magnetometer, so the browser has no heading to show.
Does it point to true north?
No, to magnetic north. The difference, declination, is usually a few degrees and depends on your location.
Why is my compass inaccurate?
Magnets in cases or mounts, metal and electronics distort the reading. Move away from them and move the phone in a figure-of-eight to recalibrate.
Is my data saved?
No. Sensor readings are used only on the page and nothing is stored or sent.