Govee Hygrometer Thermometer, Mini Wireless Thermometer Bluetooth Humidity Sensor with Notification Alert, Data Storage and Export, 262ft/80M…

I have three old hygrometers, and they all give wildly different readings (as I write this, I see 69%, 54% and 62%). We have some mould problems, and I wanted to know which rooms were above 55%, so I decided it was time to get better hygrometers. Nobody seemed to be promising better than ±1.5%, and those were prohibitively expensive, so I decided to settle for ±3%. This Govee hygrometer won due to the fact that I could record its periodic Bluetooth broadcasts using open source software on my computer without needing to depend on any apps (search for goveebttemplogger if you are interested). I ended up buying four!

Once I received my new hygrometers, my first question was: are they accurate? They claim ±3%, but can I trust that claim? How do I test them without paying a fortune for a professional calibration? I don’t have any known-accurate hygrometer to compare. So I set up some saturated-salt solutions inside a thermostatically-controlled car food cooler/heater and logged the results. I used sodium chloride (75.47% at 20℃), magnesium nitrate (54.38% at 20℃), and magnesium chloride (33.07% at 20℃). My application was mould inside my house, so I was interested in humidities between about 75% (we rarely see inside humidity above this) and 35% (this is the lowest setting on our dehumidifier). We tend to keep our living areas between 15℃ and 25℃, and even unused rooms tend to stay between 5℃ and 35℃, so I tested at 5℃, 15℃, 25℃ and 35℃ for all three salts – 12 tests in all, and each test took about 24 hours to stabilise.

The results surprised me. At 20℃ (and between 33% and 75% humidity) all four Govee hygrometers were within ±0.5%. Over our common range (from 15℃ to 25℃ and 33% to 75% humidity) the measurements were within ±1%. Over the entire range (from 5℃ to 35℃ and 33% to 75% humidity) the measurements were within ±2%.

I dare say that at more extreme temperatures the accuracy may only be ±3% as advertised, but if you only want to measure at comfortable temperatures then these hygrometers are surprisingly accurate!

Bluetooth range is excellent: about 10m through internal (plaster) walls. At further distances some readings still succeed, but become more sporadic.

My only complaint is the lack of availability of replacement batteries – the CR2477 cells seem to be quite rare.

Overall I am extremely pleased with these, and have ordered some more!

I have had this blue tooth hydrometer/thermometer for over a year. Easy to calibrate and so good, I bought three more.

I have two of these and they work a treat. I also have two of the larger WiFi models that I find are better, but these are where I started and they’re great. They connect to your phone via bluetooth and the batteries seem to last for ages.

This works well it didn’t quite have the range I needed so ended up buying a Wi-Fi one later but that is more my lack of understanding at purchase on how it worked. I am using in my chicken egg incubator to measure temp and humidity and is a great back up for my Wi-Fi one or to put in my second incubator. The only issue is my area is a distance from my house and I have to physically go up there to download the reading but when I do I get all the historical information downloaded to my app. I do like the Wi-Fi one better as I can get a reading no matter where I am every 10 minutes (even off property). But overall very happy, smooth transaction, easy to use and arrived quickly.