How to find hidden cameras in an apartment, hotel room or Airbnb

A hidden camera in a rental apartment or a hotel room is not a theory. Since April 2024 Airbnb has banned cameras inside listings worldwide, because there were enough cases to change the rules. The cameras that get found are almost always ready-made products: a smoke detector with a camera, a USB charger with a camera, an alarm clock with a camera. They cost 30-80 dollars and anyone can buy them. This guide shows how to find hidden cameras with methods that work, and in what order to use them.

Where hidden cameras are placed most often

A camera needs three things: a view of what it records, power, and room for a lens. That gives you the list:

1. Smoke detector and motion sensor on the ceiling. A view of the whole room, power, nobody looks up.
2. USB charger in the socket, power strip, lamp power adapter. Power forever, the lens in the "LED" hole.
3. Alarm clock, clock, Bluetooth speaker, digital photo frame on the bedside table. Pointed at the bed, because the bedroom is target number one.
4. Coat hook, hanger, toilet paper holder in the bathroom or a changing room. Cameras in these housings are bestsellers on marketplaces.
5. Router, TV box, thermostat, light switch. Electronics inside electronics surprises nobody.
6. Plush toy, flower pot, a book on the shelf, a cosmetics jar. Battery powered, they run for hours to days.
7. Two-way mirror. Rare, but you check it with a finger: on a real mirror there is a gap between your fingertip and its reflection, on a two-way mirror there is none.

To record anything, every camera needs a lens opening. That is its weak point. The opening is 1-2 mm wide and looks like an LED, a screw or a dot on the housing.

How to spot the lens: the reflection method

A lens reflects light differently from the plastic around it. Under the right lighting it shines as a bright, blue-violet point.

The home version: close the curtains, switch off the lights, take your phone's flashlight and hold it next to your eye so that you look along the beam. Slowly sweep suspicious objects from 30-100 cm away. You are looking for a small, sharp glint that stays in one spot when you move your head slightly. Reflections from plastic are blurry and move with you.

Limitations: it needs darkness, close range and patience. It works, but after a 12-hour journey few people do it thoroughly in a hotel.

A lens finder does the same from several meters away and in normal light: a ring of LEDs shines at the object and you look through a filter in which a lens shines like a star while everything else fades. One pass around the room takes a minute. It also finds cameras that are switched off and ones that record to a card without transmitting anything, because it looks for glass, not for a signal.

How to check whether a camera is streaming over WiFi

Most cameras sold on Amazon and AliExpress are IP cameras. They connect to the WiFi of the property or create their own hotspot and send video to the owner's app. You have two options:

• The device list on the network. If it is your own apartment, log in to the router and go through the list. In someone else's property, use a network scanning app (for example Fing) after connecting to the WiFi you were given. Names like "IPC", "Cam", "HiCam", "ESP32", or a manufacturer from the list of Chinese module makers, are candidates.
• A WiFi detector. Listens on the 2.4 / 5 / 6 GHz bands and shows transmitting devices nearby, including those connected to a network you do not know and camera hotspots. The signal grows as you approach the source, so you can walk right up to the object.

A camera can also record locally to a card and transmit nothing. Then a WiFi scan will not show it, but the lens will. That is why you do both.

What not to do

• "Hidden camera detector" apps that use the magnetometer or an "infrared scanner". The magnetometer detects magnets and cables in the wall. The front camera of a phone sometimes shows the infrared LEDs of night-vision cameras, but most pinhole cameras have no IR illuminator and phones have IR filters. It is a lottery.
• Taking housings apart and ripping smoke detectors off the hotel ceiling. If it is a normal detector, you pay for the damage. Lens and WiFi first, then a conversation with the staff.
• Taping over everything "just in case". You cover two objects and the camera is in a third.

A 10-minute sweep of a hotel room or an Airbnb

1. Before you unpack: walk around the room and count the objects from the list above. Pay attention to whatever points at the bed, the shower and the desk.
2. Check the smoke detector, the chargers and the alarm clock up close. Look for a 1-2 mm hole with no reason to be there.
3. Close the curtains, switch off the lights and do a pass with the flashlight or a lens finder. The bathroom separately.
4. Connect to the property's WiFi and run a network scan. Write down unknown devices.
5. If you have a WiFi detector: walk along the walls and past the shelves and watch where the signal rises.
6. Found something: do not touch it, photograph it, report it to the staff or the host and ask for another room. On Airbnb report it through the app; that is the basis for a refund. For intimate recordings report it to the police: it is a crime.

A camera detector: what it should do

If you travel regularly, rent out an apartment or have a reason to check your own home, you need a device that does two things at once:

• optically finds lenses, including switched-off cameras and ones recording to a card,
• shows devices transmitting in the WiFi bands, including outside your own network.

Cheap "RF detectors" for 15 dollars beep at every phone and router. Without a screen you do not know what is beeping. A screen with a list of detected devices and signal strength cuts the search from half an hour to minutes.

Frequently asked questions

Can a hidden camera record in the dark? Yes, if it has an infrared illuminator. Then, in complete darkness, its IR LEDs are sometimes visible through the front camera of a phone as violet dots. Pinhole cameras without IR only record in light.

Does a camera in a smoke detector work as a smoke detector? Usually not. No vents for smoke, no test button or no reaction to the button is a signal.

How do I tell a lens from an LED? A lens is glass, an LED is matte plastic. In a flashlight beam, glass gives a sharp point, plastic a blurry patch.

What about cameras in a car? The same rules: lens plus power. Check the mirror, the reversing camera, the cigarette lighter socket and the OBD port.

A bug without a camera? A separate topic and separate methods: Bugs in your home: how to find a listening device.