Can you imagine being alive before 1902? You would’ve had no internet, no TV … oh, and no air conditioning, because it wasn’t introduced until that year. Thankfully, we 21st-century folk have plenty of modern marvels — AC, dehumidifiers, electric fans — to keep us comfy on those particularly brutal summer days. And if you want to ensure that those essential appliances are doing their jobs, we’ve got another modern-age wonder for you: the No. 1 bestselling ThermoPro Digital Hygrometer and Thermometer. It monitors the temperature and humidity in your home so you can take action to keep them at optimal levels. Also cool: It’s marked down to just $9 at Amazon.

Why is it a good deal? 💰

This is about as low as the price on this has gone all year — and even without the discount, it would be an eminently reasonable outlay considering you’ll use it daily. Plus, you can’t put a price on comfort during a hot, muggy summer. (Or winter, for that matter; this will let you know when your home heating system is making things too dry!)

Why do I need this? 🤔

If you, like many of us, are trying to cut down on your energy bill, you probably don’t have your cooling appliances on full-blast 24/7. And while temperature is easier to feel, you might have a more difficult time discerning how humid your house is at any given moment. That’s where this hygrometer comes in.

We all know that temperature control is important for comfort, and while humidity can play a part in that too, it’s also an important element when it comes to things like growing plants or musical-instrument maintenance. Not to mention, humidity can have both beneficial and adverse effects on some health conditions. Oh, and there’s always the issue of mold, which thrives in wetter conditions (’nuff said).

With its minimalist, easy-to-read screen, the ThermoPro displays just two things: temperature and humidity. (Oh, and there’s a fun smiley face that pops up when your home has struck the ideal balance between the two.) According to the brand, the readings are updated every 10 seconds so you’ll always have the most accurate info. When it’s unsatisfied with your home’s levels, the smiley face will don a less happy expression to let you know your dehumidifier/AC needs to be turned up or down.

As far as placement goes? You can stand it up on a table, mount it to a wall or stick it to your fridge via its magnetic backing.

What reviewers say 💬

This unassuming device has racked up over 47,000 perfect ratings from Amazon customers, who praise its reliability and versatility.

Pros 👍

“I like the size of these thermostats,” said one cool customer. “They are small, but the numbers are big and easy to read from a distance. I like to know the temperature of the environment around me, so I put them in my kitchen, bedroom and the patio. They can stand on a flat surface or be hung on a wall.”

“I have a lot of plants in my home and temperature and accurate humidity levels are important for the health of the various plants,” shared this green thumb. “These work very well and appear to be accurate. They are small enough not to be intrusive to the surrounding decor.”

“Being in South Florida, I found it a must to keep an eye on humidity levels,” explained a third buyer. “I live there part-time and came back to mold and mildew after summer because there was too much humidity … I bought these to measure the levels while I’m there, and they seem to be very accurate and helpful. I keep one at each end of my home.”

Cons 👎

“My only complaint is that it is too easy,” said a mostly satisfied shopper. “You simply put a battery in and that’s it, no power button. … I just wish it had a power button to conserve battery, but it only takes one AAA, and I can always take the battery out in between uses if need be. It also seems very accurate, which is an obvious pro. Overall, I am very satisfied!”

“It would’ve been better if it had [an] LED light to be able to read it at night,” wrote a final fan. “But overall it’s really nice. … It’s very easy to read, it gives the accurate temperature.”

Amazon

For a buck more, you can get this doodad in black. 

$10 at Amazon

Of course, knowing your home’s running damp won’t do you much good without a dehumidifier…

Amazon

This little wonder is small enough to place on your desk or nightstand and can provide coverage for spaces of up to 215 square feet. It was designed to work quietly, yet efficiently, and at just 8.5″ x 6″, it’s perfectly portable for bringing on the go. 

“We had a musty smell in our basement bedroom because of excess moisture,” shared a reviewer. “This little machine took care of the problem. It’s quiet, so we leave it running all the time and clean out the water reservoir about once a week.”

$38 at Amazon

If you have Amazon Prime, you’ll get free shipping, of course. Not yet a member? No problem. You can sign up for your free 30-day trial here. (And by the way, those without Prime still get free shipping on orders of $25 or more.)

The reviews quoted above reflect the most recent versions at the time of publication.

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