SMARTRO SC42 Professional Digital Hygrometer Indoor Thermometer Room Humidity Gauge Pro Accuracy Calibration

I picked up the SMARTRO SC42 Professional Digital Hygrometer about two months ago to monitor my master bedroom because of bathroom with shower. This thing is impressive right out of the box. The 3.5" LCD screen is large and clear, with big digits that are easy to read even from across the room. The touch-activated backlight is a nice touch — it lights up for about 10 seconds when you tap the top, perfect for checking at night without turning on a lamp. Accuracy seems spot-on. It uses industrial-grade sensors (Swiss-made, according to the specs) and updates every 10 seconds. I compared it side-by-side with a couple of other thermometers/hygrometers I own, and it consistently matched or beat them. Temperature is within ±0.5°F and humidity within ±2% RH, which is excellent for this price range. I love that it shows 24-hour and all-time high/low records too — super helpful for tracking how my AC or humidifier is doing. It also has a comfort indicator that tells you if the room is too dry, too humid, or just right. Setup was basically plug-and-play (2x AAA batteries, not included). It comes with a stand, magnetic back, and hanging hole, so you can place it anywhere. No real complaints so far — battery life is solid, and it feels well-built. If you want a reliable indoor consumer thermometer/hygrometer this one is a winner. Highly recommend.

Have needed this forever. Works great, gives me a more accurate read in the house (which is a metal home). Shows temperature and variations. Has easy to read "humidity" section. Did not realize it had a magnet until I put it close and it basically jumped out of my hand to the wall...so I can guess it is a good one...Worth the money. Have not used the bluetooth and probaly will not.

Works great. The size is perfect for the countertop. Small but very easy to read.

I do wish they had an option that put the temperature in BIG NUMBERS and the humidity in small numbers, so loses one star for that for our needs anyway. Well, it is sold as a hygrometer, not as primarily a thermometer, so... Comparing with an expensive pro thermometer, it was spot on.

Just got it today based on all of the reviews and I'm extremely Happy with my purchase! Super Easy to set up, literally I put the batteries in and it did whatever it had to do on its own! I Love that it comes with magnets attached and a little stand. I purchase the two-pack and stuck one to the fridge via the magnet and one in another area on its stand. Love the light button to make it bright when you need to see it, Love the Large Numbers, Temperature monitoring was spot on.... I can tell this will function perfectly and the batteries will last quite a while because the light goes to a dimmer mode until you need to make it brighter. We have Golden Retrievers with double coat fur and I'm always cold and can't tell if their rooms are too hot & humid... so these are perfect for each area they are in so I can keep them comfortable! Just got them today and already Love them! Great Price too! I would Highly Recommend and would purchase again! It was delivered FAST too.

I set this in my humidor and it took a couple hours to reach the rh level of the humidor. I have a couple of other brands in there already so I know what the temp and humidity should be. I calibrated it once it reached the temp and humidity I knew was in there. 3 hours later cigars are 68 temp and 66 humidity. Holding the numbers solid. However, if I leave the door open too long and the rh numbers drop, it will take it a few hours to settle and read the proper rh again. I mean it creeps back up on the display. Nevertheless, it is working very well.

This is a solid little unit that provides helpful/accurate information. Easy to read numbers and graphs, and even has a light when neeeded! I had no idea how little indoor humidity I had in the winter time until I got this. Now I'm easily able to guage/achieve a more healthy indoor environment. A must have for cooler/cold climates. Would purchase again and am considering giving as a useful gift.

I’ve had 2 of the Smartro SC42’s for 4 yrs now one in my rifle safe & one in my Large pistol safe. They are Excellent & Accurate. It’s such a piece of mind to open your safe & know the Temperature & Humidity are where they need to be. If one of them ever fails I will replace with the same meter. I love knowing the guns are being stored properly. A must have for owners of multiple firearms.

I use it for keeping my acoustic guitars at the right humidity levels (40~50%) which need an ajustable calibration offset controls (use humidity pack for control reference). Works fine and nice to have a readout backlighting when needed… (Cheaper hygrometers have no controls and can often be inaccurate up to 10%…)

I brought one checked it via a salt test bang on 75% brought another same as bang on 75%. Very pleased with the accuracy, very easy to use & has a decent magnet to hang up. to verify if your meter is correct put it in a plastic container with a cap filled with salt add a very small amount of water to the salt so you can still pick it up & it doesn’t run, seal it properly leave it a full 24hrs and it should read 75% if not it’s out & needs calibration )

He tenido muchos de estos y este es muy preciso, además se ilumina al moverlo, vale la pena el dinero q vale.

Working great so far and I’ve had for a few months now. Accurate measure and backlight is very bright but not blinding. Great display and easy to read.

Ottimo igrotermometro. Alla fine ne ho acquistati tre…. Dopo averne resi due di altro produttore che non ho trovato affidabili e che non permettevano la calibrazione se non in un piccolo range ristretto, inutile nel mio caso. Mentre questo permette una calibrazione senza vincoli !!! Ottimo prodotto.