Check compass calibration on a phone while charging
See whether charging affects your phone's compass, how to tell interference from calibration trouble, and what to try before relying on its direction.
Your phone’s compass may point the wrong way, drift, or jump when the phone is connected to a charger. Before trying to recalibrate it, check whether the charger, cable, case, or nearby metal is affecting the reading.
Use the Sensors Test to view compass readings in your browser. Compare the phone in the same position while unplugged and charging. This can help you tell a calibration issue from nearby magnetic interference.
Check the compass while charging
- Open the Sensors Test on your phone. If the browser asks for access to a sensor, allow it. If you do not see compass readings, check the result section below.
- Set the phone on a nonmetal surface, such as a wooden table, away from a laptop, speakers, metal objects, and magnetic accessories. Unplug the charger and wait for the compass reading to settle.
- Keep the phone flat and still. Slowly turn it in place and watch whether the compass reading changes smoothly as the phone turns. Avoid judging it while you are moving the phone between rooms.
- Return the phone to the same position and direction. Connect the charger, keeping the adapter and cable in the same place each time, and watch the reading again.
- Repeat the comparison with the charger and cable moved a few feet away from the phone. If possible, test a different outlet or charger, changing only one thing at a time.
A nearby charger does not have to be defective to affect a compass. Current flowing through a cable and magnets in a case or charging accessory can alter the magnetic field around the phone.
What the result means
The reading is steady unplugged but changes when charging
The charger, cable, or their position is probably interfering with the compass. If moving them away makes the reading steady again, calibration is unlikely to be the main problem. Use the phone away from the charger when you need a reliable direction, or try a different cable and adapter.
The reading is steady both plugged in and unplugged
The compass is behaving consistently in this spot. That does not prove it is perfectly calibrated everywhere, because nearby metal and magnetic fields can change the reading in another place. Check the direction outdoors or away from electronics before assuming the phone has a fault.
The reading jumps or drifts in both tests
First move away from metal furniture, speakers, magnetic phone mounts, and other electronics. If the reading remains erratic in several locations, calibration may need attention, or the phone’s compass sensor may be unreliable.
The compass reading is missing
The phone or browser may not provide compass data to the page, or sensor access may be blocked. Some devices do not include a compass sensor. If the browser has a site permission for motion or orientation sensors, check that it is allowed, then reload the page.
The reading is stable but the direction seems wrong
A stable reading can still differ from the direction shown on a map. A compass responds to magnetic north, while maps may adjust for the difference between magnetic and true north. Compare it in an open area, and check the phone’s built-in compass or navigation app before treating a small difference as a fault.
How to fix an unreliable compass
- Move the charger away. Keep the phone, charging cable, and power adapter separated while checking direction. Do not rest the phone directly on a wireless charger or on top of a metal surface.
- Remove magnetic accessories. Take off a case with a magnetic ring, wallet, or mount, then compare the reading again. Also move away from magnetic stands and nearby speakers.
- Calibrate away from the charger. If the phone’s compass app or system displays calibration instructions, follow them in an open area away from metal and electronics. A figure-eight motion is commonly requested, but use the instructions shown for your device rather than repeating it beside the charger.
- Check compass access. On an iPhone, open Settings › Privacy & Security › Location Services › System Services and check Compass Calibration, if that option appears. On Android, there is no single calibration menu used by every phone. Check the compass app’s permissions under Settings › Apps › [compass app] › Permissions, and follow any calibration guidance from the phone maker.
- Restart the phone and retest. A restart can clear a temporary sensor or browser problem. Reopen the test and repeat the plugged-in and unplugged comparison in the same location.
- Try another charger and cable. If the compass changes only with one charging setup, replace or reposition that accessory. If it changes with several chargers, test away from all charging equipment to rule out the room and nearby objects.
When the phone may need service
If the compass remains unstable in an open area with the case removed and charger far away, restart the phone and check for system updates. If the built-in compass also behaves erratically, the issue may be with the phone’s sensor rather than the browser. Contact the manufacturer or a repair shop, especially if the phone was recently dropped or repaired.
For a fair comparison, keep the phone’s position and direction the same while changing only the charger setup. That makes it easier to spot interference without mistaking a change in location for a calibration problem.
