Aranet4 HOME vs Aranet Radon Plus

Aranet Radon Plus wins narrowly, with an even higher owner rating, roughly 7 years of battery life versus up to 4, and an IP20 rating. But these siblings measure different gases, so the practical answer is: Aranet4 HOME for CO2 and ventilation, Aranet Radon Plus for radon.

The headline sensor. The Aranet4 HOME tracks CO2 with a benchmark NDIR sensor, telling you when a room needs ventilation. The Aranet Radon Plus tracks radon with readings owners say match mail-in lab tests. Both also measure temperature, humidity and atmospheric pressure.

Very. Both use always-on e-ink displays, sync over Bluetooth to the same style of app with history graphs, run on two AA batteries for years, integrate with Home Assistant (and nothing else), and carry 2-year warranties. Neither has Wi-Fi or cloud sync.

The Aranet4 HOME: it is the smaller, lighter unit and is designed to travel, from offices to classrooms to airplane seats. The Aranet Radon Plus is meant to sit still, since radon readings need time in one place to average properly.

Choose Aranet4 HOME if you want to manage ventilation and freshness: CO2 spikes tell you when to open a window, and its accuracy, portability and battery life make it the reference in that role. It also confirms temperature and humidity alerts.

Choose Aranet Radon Plus if radon is your concern, for a basement, a radon-prone region or mitigation follow-up. It pairs lab-matching accuracy with a scientifically guided radon alarm, an e-ink readout and batteries that last around 7 years.