2026-09-08
Compass Accuracy in the UK: Magnetic Declination and Calibration
The most common reason a qibla reading is wrong is not the calculation but the sensor. A phone compass is a magnetometer, and magnetometers react to anything that generates or distorts a magnetic field. Two minutes of preparation turns an unreliable reading into one you can trust.
Two different norths
True north is the direction of the Earth's rotational axis, and it is what the qibla calculation uses. A magnetic compass points at the magnetic north pole, which sits in the Canadian Arctic and drifts. The angle between them, seen from where you stand, is the magnetic declination. Britain is fortunate here: the declination is currently small, roughly one to three degrees west across most of England and Wales, somewhat larger in western Scotland and Northern Ireland. Compare that with the United States, where it reaches fifteen degrees in both directions.
Applying the correction
With a west declination you add it to the true bearing to get the magnetic bearing. So a true qibla of 119 degrees in a place with 2 degrees west declination becomes 121 degrees on the compass. Getting the sign backwards doubles the error, which is the most common mistake people make. On every city page we do this for you and print the magnetic reading directly.
How to calibrate
Hold the phone free in your hand and move it in a figure-eight for several seconds so it rotates around all three axes. Then hold it flat, screen up. Repeat this if the reading jumps around or if the system prompts you. Calibration is not permanent — it drifts, and it is worth redoing whenever the needle looks unsteady.
What actually ruins readings
Magnetic clasps on phone cases are the single most common culprit, followed by car mounts and wireless charging pads. Then come speakers, headphones, laptops, radiators, steel-framed buildings, reinforced concrete floors and vehicles. In a multi-storey car park or next to a radiator no compass is reliable. Step to a window or outside, and take the case off if it has a magnet in it.
The check that needs no compass
At the moment Dhuhr begins the sun is due south. That is solar noon, not one o'clock on a summer clock — the exact time is on every one of our prayer times pages. Face the sun then and you are facing true south, with no magnetic correction involved at all. From that reference you can lay off your city's qibla angle and mark it once for good.
If your device has no magnetometer
Many tablets and some budget phones have none. The calculated angle still applies; you simply transfer it to a real compass or use the solar method. Britain's small declination makes an ordinary hiking compass more than accurate enough for this purpose.