Netatmo Smart Indoor Air Quality Monitor (NHC-UK) review
A cheap, permanently plugged-in CO2 reading in a room where noise levels are also worth knowing.
By Tom Calder · Price last checked 20 Sep 2026, 12:29 BST · price-tracked
The cheapest genuine CO2 monitor here, and the only one that also measures noise — a real differentiator in a home office or a room next to a busy road. It is old hardware for the money, it has no screen, and it is mains-only, so it goes dark the moment the power does. Its "Asthmatic", "Baby" and "Family" app profiles are adjustable alert thresholds, not health features, and should not be read as anything more.
as of 20 Sep 2026, 12:29 BST · Details
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- Cheapest route to a real CO2 reading, from around £68 at the keenest UK sellers
- Noise-level sensing that nothing else on this page offers
- Wi-Fi straight to the app plus Apple Home compatibility, with no hub to buy separately
- Mains-only via USB adaptor with no battery, so it stops working in a power cut
- No screen — readings live in the app, with only a colour-coded LED on the device itself
- Apple Home compatibility is a platform feature, not a safety or accuracy credential
Who shouldn't buy this
you want a CO2 figure you can read at a glance without your phone — the Aranet4 Home has the display for it.
Key specs
| Measures | CO2, temp, humidity, noise level. No PM2.5, VOC, radon or CO. |
| Display | No screen — press the top for a colour-coded LED summary |
| Connectivity | Wi-Fi to the Netatmo app, with Apple Home compatibility |
| Power | Mains only via USB adaptor — no battery, must stay plugged in |
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Alternatives to consider
as of 20 Sep 2026, 12:29 BST · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.as of 20 Sep 2026, 12:29 BST · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.as of 20 Sep 2026, 12:29 BST · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Want this cheaper?
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