A hygrometer just might be the key to maintaining a consistent and comfortable humidity level in your home — for yourself, pets, family, plants, or anything else that might benefit from having a specific amount of moisture in the air. Also known as humidity monitors, hygrometers take the guesswork out of tracking humidity levels and offer an accurate read on current air conditions with a user-friendly interface. Whether you prefer an analog dial or digital display, the best hygrometers offer an accuracy within 5% relative humidity — and some models offer a near-perfect accuracy within 1%.
Most modern hygrometers fall into one of two categories: mechanical, or electrical (also known as digital). Aside from accuracy, a legible interface is the most important consideration for a mechanical model, and one with a sizable dial and clear measurement markings can be easier to read. One major perk of mechanical models is that they don’t require a power source. However, you should consider opting for an electrical hygrometer with a digital display if you prefer a more precise reading. Electrical hygrometers often measure the humidity levels down to the decimal, and they are the most commonly available option on Amazon.
If you want something basic to give you an up-to-date read on humidity levels, a budget-friendly mechanical hygrometer with an analog dial might be all that you need. However, for a few more dollars, you might prefer a hygrometer with additional features that make it even easier to track (or control) humidity levels. There are also smart hygrometers that pair to your phone, which allows you to monitor your hygrometer from just about anywhere. And if you’re looking for a tool that can help you track and maintain humidity levels? Opt for a humidistat that you can connect to a humidifier or dehumidifier.
With all this in mind, here are four of the best hygrometers that you can snag to monitor humidity levels. (And don’t forget to regularly calibrate your hygrometer to make sure you’re always getting the most accurate reading possible.)
1. The Most Accurate Hygrometer
- Accuracy: Within 1% of relative humidity
If precision is of utmost importance to you, this highly accurate hygrometer is worth consideration. It offers a near-perfect accuracy reading of within 1%, making it the most sensitive option on this list. This compact device is designed for use in humidors (cases for storing cigars), but reviewers have used it to monitor humidity levels in spaces like terrariums, guitar cases, and chicken egg incubators, too. One reviewer wrote that while “most of the popular ones for egg incubators are junk, this one is different and works great.” Meanwhile, another reviewer noted, “I use this for my wooden guitar, which needs to be kept humidified between 45% and 55%, and this hygrometer does the job.”
Despite its size, it features a legible interface that provides you with lots of information at a glance. You’ll find measurements for both humidity and temperature levels (with the option to toggle seamlessly between Celsius and Fahrenheit), plus three days’ worth of data on the highs and lows. It requires a CR2032 battery, but one is included with your purchase.
Positive Amazon review: “The reading is accurate and its easy to use. I keep mine in my guitar case to monitor temperature and humidity for my guitar. It’s great for this purpose and a nice size for it too.”
2. The Best Mechanical Hygrometer
- Accuracy: Within 5% of relative humidity
With a traditional analog face, this budget-friendly hygrometer is a solid option if all you need is a basic yet reliable tool to tell you the humidity and temperature levels (the latter of which are listed both in Celsius and Fahrenheit degrees on the dial). Just below the relative humidity gradation, you’ll also notice three color-coded segments to signify if an environment is too “humid,” too “dry,” or at a “normal” level. Constructed from stainless steel and glass, this one’s designed for use either indoors or outdoors. Plus, it doesn’t require a battery to work.
Positive Amazon review: “I am very happy with it. I checked it outdoors against the airport hygrometer and it is right on. It is big and easy to read from 8 ft away.”
3. The Best Smart Hygrometer
- Accuracy: Within 3% of relative humidity
For folks who prefer a tech-savvy option, look no further than this smart hygrometer, which allows you to monitor air conditions remotely with your phone (instead of with an on-unit display). As long as you keep the sensor in a space with reliable Wi-Fi or Bluetooth connection, you can keep a close eye on humidity and temperature levels wherever you are. The app for the hygrometer is compatible with iOS and Android devices, and it provides updates to your phone in real time (or every two seconds, to be exact). You can also preset both humidity and temperature levels to your desired range. If either falls out of range, the app will let you through a push notification. As a bonus, it retains data of highs and lows for up to two years. This hygrometer runs on three AA batteries.
Positive Amazon review: “I bought this for a freezer in the garage. The initial set up with the app was a little more difficult than I thought it should be. Once up and running though it works great! I am able to check the temperature wherever I am. I would recommend!”
4. The Best Humidistat For Your Humidifier & Dehumidifier
- Accuracy: Within 3% of relative humidity
This hygrometer performs double duty by monitoring and maintaining humidity levels in enclosed spaces. Using the digital display, you can track current air conditions and preset humidity levels to your desired range. Then all you have to do is connect it to a humidifier, dehumidifier, or both (100 to 240 volts) — and the hygrometer can automatically control those appliances to adjust the humidity as needed. Think: terrariums, basements, or anything that stores humidity-sensitive animals or other objects. If humidity levels are far out of range, the hygrometer will let you know by sounding off an alarm.
Instead of batteries, this hygrometer plugs into an outlet. Just keep in mind that since this hygrometer cuts or restores power to the appliances (sort of like a power strip), it will only work with appliances that will automatically turn to an active setting when power is restored. One user noted that you can use it “with any humidifier that is on/off with [electricity] (as opposed to having to turn on with a button every time.)”
If you could use a hygrometer that can monitor and adjust both the humidity and the temperature levels, Inkbird offers an option with a built-in thermostat for a little more.
Positive Amazon review: “This makes it to where I can set humidity and it will turn my dehumidifier or humidifier on or off to maintain my set level..a must have. Easy to use and reliable.”