Scope: this page is for someone who believes a tracker has been placed on their own vehicle or belongings. It covers finding one. We do not provide guidance on tracking people.
First, the thing that decides your method
There are two kinds of tracker and they are found in completely different ways.
Bluetooth tags — AirTags and similar — are found by your phone, free, using the built-in unknown-tracker scan. That is by far the best tool and we cover it here. Start there.
Cellular GPS trackers are invisible to that scan, because they do not broadcast Bluetooth — they talk to a cell tower. No phone scan on either platform will ever see one.
This page is about the second kind.
What you are looking for
A consumer magnetic cellular tracker is roughly the size of a matchbox to a deck of cards, usually black, usually in a hard plastic or rubberized case, and usually held on by a strong magnet. Hardwired units are smaller and have wires going into the vehicle's loom. OBD units plug into the diagnostic port under the dash and are the easiest to spot.
Search the easy places first
The OBD port. Under the dash on the driver's side. A dongle plugged in there is the single most common installation and takes two seconds to check.
Under the car, with a torch. Magnetic units go on flat steel: the chassis rails, inside the wheel arches, behind the bumpers, under the boot floor, on the fuel tank shield. Run a hand along surfaces you cannot see — a magnet is obvious by touch.
The boot. Under the floor panel, in the spare wheel well, inside the side trim, behind the rear light clusters.
The cabin. Under the seats, seat-back pockets, the glovebox, the center console, under floor mats, inside door cards if any are loose.
Then search the places that need more effort
Hardwired installs. Look for wiring that does not belong: a pair of wires tapped into the fuse box with a piggyback fuse, or spliced into a loom behind a kick panel. A neat install is hard to spot; an amateur one usually has electrical tape on it.
Behind trim panels. Kick panels, A-pillar trim, under the steering column shroud, behind the glovebox liner. These need tools and patience.
In the engine bay. Less common because of heat, but a weatherproof unit can be zip-tied to a loom or tucked behind a liner.
Inside the rear bumper. A popular spot for magnetic units, because plastic bumpers do not block signal and nobody looks inside them.
On RF detectors, honestly
An RF detector sweeps for radio emissions and can find a cellular tracker — but only while that tracker is actually transmitting.
Here is why that matters. Most cellular trackers sleep when the vehicle is stationary to save battery, waking on motion. So a careful sweep of a parked car can easily find nothing while the tracker is sitting there, asleep.
Two practical implications. Sweep while the vehicle has just been driven, when a motion-woken device is most likely to report. And treat a clean sweep as weak evidence rather than proof — a physical search is more reliable.
Cheap RF detectors also false-positive on almost everything: a router, a phone, a key fob, LED lighting. The genuinely useful feature on these devices is often the magnetic field detector, which finds a magnet-mounted unit under a car regardless of whether it is transmitting.
Signs worth noticing
Unexplained battery drain on a vehicle that previously held charge, which can indicate a hardwired device.
Fresh marks in dust or road grime under the car — a clean rectangle on a dirty chassis rail is worth a second look.
Trim that no longer sits flush, or screws with fresh tool marks.
A piggyback fuse in the fuse box, or wires that do not match the factory loom colors.
If you find one
Do not remove it immediately if you may involve the police. Its position and its presence are evidence, and in some cases its SIM and serial can be traced.
Photograph it in place, from a distance and close up, including any serial or model number. Note where it was. Then contact local law enforcement.
Tracking a person without consent is unlawful in many places — California Penal Code § 637.7, for instance, prohibits using an electronic tracking device to determine a person's location or movement, with exceptions where the registered owner, lessor or lessee consents and for lawful law-enforcement use, and a violation is a misdemeanour. Other states differ. This is not legal advice.
If you believe the person responsible is a partner, former partner or family member, a domestic-violence advocacy organization can help with the situation around the device, which is usually the larger problem. A tracker found is rarely the whole of it, and this is not something to handle alone.
If you cannot find anything but still believe you are being followed
Consider that location can leak without any hardware at all: shared location on a phone, a family-sharing account, a connected-car app, a shared cloud account, or a vehicle's own built-in telematics.
Those are often more likely than a physical device, and they are worth checking: the sharing settings on your phone, who has access to your accounts, and whether a connected-car app is paired to somebody else's login. A professional sweep is also an option for a vehicle you genuinely cannot clear yourself.
