Aranet Radon One Review: A 10-Minute Radon Reading on Seven Years of Batteries
E-Ink radon monitor with a WHO-referenced colour alarm, running on two AA cells and pairing over Bluetooth.
The Aranet Radon One is a single-purpose instrument: it measures radon, the radioactive gas that is the leading cause of lung cancer in non-smokers, and does nothing else. What it does bring is convenience, with an always-visible E-Ink display, a colour-coded alarm referenced to World Health Organization guidance, seven years of life from two AA batteries, and recorded history so you can see how levels move through the day and the seasons. The limitation is connectivity: Bluetooth only, with Home Assistant as the single supported platform, so there is no Wi-Fi, no cloud dashboard and no voice assistant.
- Basements and ground floors
- Radon-prone regions
- Home Assistant users
- Long-term radon tracking
Pros
- Dedicated radon sensor with a fast response time
- E-Ink display readable without a phone
- Colour-coded radon alarm referenced to WHO guidance
- Seven year battery life on two AA cells
- History records for tracking trends over time
- Home Assistant integration
- Portable at 220 g, so it can be moved between rooms
- Two year warranty
Cons
- Bluetooth only: no Wi-Fi, so no remote monitoring from away
- Home Assistant is the only supported platform
- Measures radon only, with no CO2, particulate, temperature or humidity sensing
- IP20 rating, so indoor use only
- No mains power option
- Screen size and resolution are not documented
Who is the Aranet Radon One for?
Radon is invisible and odourless, it seeps up from the ground, and it concentrates in basements and lower floors, so the only way to know your exposure is to measure it. This monitor is for anyone living in a radon-prone area, anyone with a basement bedroom or office, or anyone who has had a one-off test come back borderline and wants continuous numbers instead. The E-Ink screen means the current level is readable at a glance without a phone, which suits a device you leave in a corner for years.
What it measures and how it warns you
Radon is the only sensor, and the display carries the reading directly. Air quality alerts use a colour-coded radon alarm referenced to WHO guidance, so you get an interpretation rather than a bare number, which matters for a gas most people cannot put in context. History records let you see trends over time, and that is where a continuous monitor earns its place over a mail-in test kit: radon fluctuates with weather, ventilation and season, so a single result can be misleading in either direction. Home Assistant support lets those readings feed into a broader smart home, for example triggering ventilation.
What to know before you buy
Connectivity is Bluetooth only. There is no Wi-Fi, no Zigbee and no Thread, so readings are collected when your phone is nearby rather than pushed to a server, and remote checking from another building is not part of the design. Home Assistant is the only supported integration: Google Home, Alexa, Apple HomeKit, SmartThings, IFTTT and Matter are all unsupported. It measures radon and nothing else, with no CO2, particulate, temperature or humidity sensing, so it complements rather than replaces a general air quality monitor. It is rated IP20, meaning indoor use only with no water protection, and it runs on batteries with no mains option, though seven years of life makes that a strength rather than a chore.
Is the Aranet Radon One worth it?
It sits at the premium end for a single-gas monitor, and the case for it rests on two things: the speed of the reading and the length of the battery life. Ten-minute response makes it practical to move around the house and compare rooms, rather than waiting most of a day per location, and seven years on two AA cells means it can simply live in the basement without maintenance. If you want one device that covers radon plus CO2 and particulates, this is not it. If radon is the specific question, it answers it clearly and keeps answering it for years.
Frequently asked questions
Does the Aranet Radon One connect to Wi-Fi?
No. It uses Bluetooth only, so readings are collected from a phone nearby. Home Assistant is the one supported smart home platform.
How long do the batteries last?
Up to seven years on two AA batteries, which is what makes it practical to leave in a basement long term.
Does it measure anything besides radon?
No. Radon is its only sensor. There is no CO2, particulate, temperature or humidity measurement.
How do I know if a reading is dangerous?
The monitor uses a colour-coded radon alarm referenced to World Health Organization guidance, so levels are shown in context rather than as a raw number alone.
Can I move it between rooms?
Yes. It is battery powered and weighs 220 g, and its fast response time makes room-by-room comparisons practical rather than requiring a full day per location.









