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Thermopro TP357W

(60 customer reviews)

$12.99 $13.77

Availability: Out of stock

Bluetooth Digital Indoor Hygrometer Thermometer with App Alert

  • Comfort face indicators】: Humidity meter features comfort face icons to indicate DRY/COMFORT/WET air conditions in an easy to understand format and allow you to adjust your humidifier or dehumidifier accordingly;
  • 260ft/80m enhanced Bluetooth range】: Humidity sensor contains an enhanced Bluetooth Technology to produce a stable, ensure you’ll always have full home coverage to monitor the temperature and humidity within your home;
  • Highly accurate and fast refresh rate】: Indoor temperature and humidity monitor is highly accurate for both temperature and humidity (±1 Fahrenheit/Celsius and ±2%), with a lightning quick refresh rate of 2 seconds;
  • Smart App with alerts】: Set a temperature and humidity range via the ThermoPro Sensor and instantly receive a phone notification if the temp or humidity levels ever fall outside of your range;
  • Temperature graph and 1 year data storage】: Thermometer indoor outdoor displays an easy to use temperature graph with a maximum 1 year time period;
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60 reviews for Thermopro TP357W

  1. HL

    seems to be working well

  2. lashlarue

    They work alright, however I found you have to be close for the temp app to register on your phone.

  3. Charlie G

    This thermometer works well. It took 20 minutes to come to an accurate readout. The display is a bit small but is easy to read. The Bluetooth app is nice and has a decent range.I’d buy it again.

  4. Melissa Lee Anderson

    These hygrometers have made growing indoors so much easier. I was always constantly opening my tent to read the humidy and temp levels to the point the zippers on my tent were getting worn out. These have fixed that problem. They have little magnets on the back so they can be attached directly on your tent poles. The Bluetooth connectivity is easy to set up and makes life much easier just being able to look at my phone and see the levels on the app. No more unzipping and zipping my tents doors multiple times a day. Super effective

  5. Ross Dunton II

    Excellent product. I keep a item in my car that will shut down at extreme temperatures. I’m able to sit in my living room and monitor the inside temperature of my car. Excellent range, thrus walls and cars.

  6. Richard of Spring Hill TN

    Like the capability and remote connection to iPhone

  7. Donna Ortiz

    Good d

  8. RandomRose

    I really like these devices. I use them in my guitar cases to monitor humidity. The accuracy is good. We have some sophisticate weather monitoring devices for capturing weather data like temp and humidity and the Tempro is measuring very close to those precision instruments. The Bluetooth feature is very handy. Just down load the App for your phone, and you can pair your Tempro device to the App via bluetooth. If you have several, an I have 4 you can name each monitoring devices. I name the devices after the guitars and I’ve also used permanent marker to write the names on the Tempros so I don’t mix them up. Then, without opening the cases, I can look on my app and see the temps and humidity of each guitar case/guitar. An inexpensive and really handy way to protect your gear.

  9. richard

    had spray foam put in my attic in south Florida. Wanted to check humidity up there while in the house. Blue tooth works great its always just a little more humid in attic than interior of house which is okay. Just want to know when I have too much humidity because mold will grow. Beats crawling up in attic to check weekly.

  10. Dan Worcester

    Easy to track over time with iPad

  11. Amazon Customer

    I like them so much I ordered two more for additional rooms. Very easy to connect by bluetooth to the Thermopro app.

  12. Nost

    I first purchased a pair of these and they both read exactly the same and accurate on temperature and humidity. I ordered a second pair and one reads accurately like the first two but the second reads 3 degrees lower on Fahrenheit and 4% lower on humidity.

  13. San

    At the end, it is all about how it fits your need. For me it was worth the money and I even bought another device like this for around the house.It ended up saving me time and allowed me to get value out of it from the start. The money was well spent, and the device performance is acceptable so far. In the past I was hesitant to buy these type of devices because of cost. I was lucky this device does what it advertises (long battery life, up to 1 year log storage, small size, and a commonplace AAA battery type.My use case is to track humidity and temperature for filament used for hobby 3D printing. I wanted to build the device myself (temp, hum, and pressure, all read over BLE, with an e-paper display and all!), but as time went by, I could not find the time to finish my ‘project’ within budget and hobby-time constraints. This device allowed me to start tracking filament use/storage life today, while I could still keep dreaming of my own device (because this product does not sense barometric pressure). Now that I use it, I dream of using a raspberry Pi to read this BLE device automatically (yes, adding another project to my pile of ‘unfinished projects’)My only downer so far is that the Android app does not allow me to save or export the data. It is not even available in the user space memory of the phone, so I can not easily extract it from the app. While I can see the plots in the app, I want to be able to save all the data to a file for later comparison. I will need (yet) another project of mine to use a Raspberry Pi to read all the data and save it. It would be nice if they update the app to at least save all the data to a file in the Android app folder, so we customers can copy it.Hope this experience helps others.For some of the comments I read, I think I know some of the answers:- The location access the app needs is because Google improved Android security awareness, and since Wi-Fi and BT/BLE scanning can be used to locate your device, the message will say ‘location’ because the app you are trying to use needs access to the BLE scan function to be able to find any of these sensors you own that are near your phone.- The 10s refresh-rate should be independent of the speed at which the sensor stabilizes to the exposed environment (response-time). I agree the manufacturer is pushing the limits of misleading by stating “10 s Fast Response” where ‘response’ and ‘rate’ are not quite synonyms. In any case, typically these devices take some time to settle due to lack of proper air flow, etc.

  14. Dan

    Thieve work great giving me alerts when the coolers are out of temp!!!

  15. Martha

    This is easy to set up and is very accurate. I didn’t sink it with my phone because it was too complicated, but I don’t need to know what the temp is in my house when I’m not there. Not sure about the humidity gauge but there’s a little smiley face so I guess that’s good. As long as he’s smiling, I’m happy!

  16. LEE


  17. tdmartin

    Downloaded the app, hit SEARCH and there it was. I can tell the temperature of the house wherever I am. I purchased three others sensors. I am going to put one outside, one under our house (we have a crawl space. It will tell me if i am ever in danger of freezing or if I have a water leak, humidity would go to 100%) and one in the attic, just for curosity. I have a solar attic fan, just curious what the temperature is.

  18. Amazon Customer

    I needed to get a thermometer for my bedroom, because we don’t have a working central AC system in our house right now. Comparing this thermometer to a nearby thermostat, it is indeed very accurate, down to the decimal. Accurate and consistent with no massive fluctuations.As for the humidity gauge, I compared it to another hydrometer in the house and it was about 2-5% off the other hydrometer which is in the range of their advertised accuracy. So no complaints with the consistency side of things, but there are some small complaints I have:-Sometimes the app takes a while to load data.-The heat index featured only in the app itself seems to only start applying when the temperature in the area reaches 80F(27C) in my experience. Im not sure how it starts to calculate a heat index, but it does indeed work.-Notifications only notify when you launch the app (this might be an iPhone problem though.)-If you use this in a room with a window AC unit, like I do, the humidity sensor might go a bit haywire, but it will still stay within accurate measurements. Example, first night with this device in my bedroom, the humidity went from 58% to 54% back to 58% to 56% etc every so often all night.In all, very happy with this purchase. Was really cheap too! Just goes to show you dont need to spend $15+ just for a simple thermometer/hydrometer.

  19. William J.

    accuracy within 1/2 degree of traceable thermometer!

  20. Sandy Korsbon

    Wanted to check and compare what my thermostat showed – turns out it was cooler in my house than I needed it to be and so have set my air conditioning to a higher temperature. It will help in the winter with setting my heat temperature as well.

  21. sash0k

    It seems handy, but not very precise. I would only use it as a device to give you a ballpark estimate.

  22. Sarah Moore

    Our AC upstairs is wonky and on its way out so I got these to monitor temperature in kids rooms while they are sleeping so I don’t have to go up and down the stairs. Seems to be very accurate. App set up was easy. Only complaint would be sometimes the app doesn’t automatically update the temp so I have to pull screen down to update but not a big deal and could be my internet. Wish I could set an alarm through app to alert me when temp goes under or over a specific number. Overall a great purchase and recommend it!!

  23. Sheri Goreham

    Easy to setup and very accurate!

  24. NYC RockGuitar

    Very close readings. ThermoPro needs to be more sensitive to temp. Tested Window AC Frigidaire 10KBTU – LOW Speed Full Cool. after 20 min, ThermoPro = 2 Degrees Celsius difference from glass thermometer (accurate scientific instrument.)Data: Glass Thermometer = 5C ThermoPro = 7C

  25. Erin J. Bates

    I’ve had other gauges in the past that didn’t last. This one is much better quality!

  26. shyawno

    Nice unit.

  27. Terry

    These are handy little units that you can place in out of the way places (like crawl space) and monitor on the app. All very straightforward and easy to use. Using them to track down a humidity problem we are having in a couple of rooms. And the crawlspace ones will be perfect to just leave there to make sure we don;t get any leaks or water under the house!

  28. Robert M.

    I cannot begin to say enough praise to these simple tools.I ordered 4, they were delived over night and setup was complete in less than 5 minutes including mounting them in their designated positions within our office space.The real time numbers on the screen are great for when I’m doing a quick walk past and want to see the zone humidity and temps. The app is very responsive to the pulling of data from each sensor. The history tracking of up to a year is just a great added benefit for when we are running our audit reports on our climate control systems.Our only possible request would be to have the ability to export the data so that we can print it on our reports without having to screenshot from our phone. This is simply a nice to have but not a necessity for us.

  29. BirdNerd

    Within a degree of each other and match the room temp as well. Size is nice for what I’m going to use them for. I also chose them because they use a triple A battery, whereas most others this size use the coin batteries.

  30. Kei Lau

    The ThermoPro APP found the thermometer 357 easily. I like the 357 using AAA battery giving it longer operational life. The APP has daily, weekly and yearly tracking. I cannot ask for more for a $12 device. It works very well with Ni-MH rechargeable AAA (at 1.2 volts). Highly recommend Panasonic Eneloop low self discharge cells. Non-rechargeable AAA works too, but not economical.

  31. Mrhappy

    I have one in most of the rooms in my house. I have Window A/C’s so the temp is different in each room. I put all 4 next to each other for a couple hours with another temp brand that I have, and they were all within .6 degrees of each other. Two were exactly the same.

  32. garden freak

    Like: fast response and delivery… easy to set up. and useUse: monitor temperature and humidity at various rooms continuously via Bluetooth.

  33. Customer 43876

    I installed my first TP357 a year ago to monitor a not easily accessible storage space. Works beautifully. While the bluetooth range isn’t great, I can monitor the unit from the comfort of a couch within the house. Well worth the dozen dollars paid. Just bought another for the basement.

  34. David La Palombara

    Top quality product-Sharp design-Works as advertised. I truly recommend this product to everyone

  35. A. Bass

    I put one of these in my basement and one in my sunroom. My phone connects to each within about 5 seconds of opening the app on my phone. I have not had any issues with blue tooth connectivity.I purchased these to monitor temperature changes over time (night, week to week, seasonally, etc) and this appears to work great for that.

  36. Amazon Customer

    Works as advertised, so far falls within the stated accuracy ranges compared to my other devices. The only thing I don’t like is the graphing for a 24 period is shown with 7 columns, which is 3.428 hours per column, sort of useless for fine tracking.But overall I’m happy with it.

  37. Iulia

    I would rate it more if it didn’t ask me for location every once in awhile. I am able to deny and I do deny. But I don’t appreciate harassment, and I don’t appreciate data harvesting, which I assume it’s trying to do.I really like that it has a chart that lets me know the historical data of temp and humidity.

  38. Ken in WA

    I got one of these to track my office temp as part of maintaining some PC and network gear.First one stopped allowing the Bluetooth connection after a day. So, filed for a return and Amazon sent a new one.Next one did the same, but also had very different numbers 2.5 degrees higher than the last one.However, in testing them I learned the Bluetooth is just fine, if you use a new battery. The included “alcaline” battery is junk and won’t support the Bluetooth function.Now my return is still happening, but Amazon is getting the one with the overly high temp back.

  39. Bernie

    I bought two. Only issue even though they both have magnet on back, One did not come with a little kick stand!

  40. Jordan Wong

    I like the unit. It appears to be very accurate and it’s easy to move around, very portable.

  41. Jonathan

    The phone app requires location services to be turned on and location permissions allowed on the app. You cannot use the app unless you turn on and allow the location service to run. There is no reason location services should be required to connect to the device via Bluetooth in order to simply check the readings.Other than that, the temp and humidity displayed on the device’s screen seem to be accurate.

  42. Rachel

    Accurate temps. Easy to read screen. Was easy to set up initially. Deleted info when moved from an office to fridge. Had a hard time getting it connected again. Won’t automatically update to app when located in fridge/freezer. Need to have door open for it to sync. Keeps data for 1 year.

  43. Julie R. Kautz

    needed to check my thermostat before replacing – this does read a couple degrees higher, so i think it is accurate.

  44. kim coop

    This was the perfect size for me. I have this placed right on my night stand table as I was having problems with my AC so I wanted to be able to see what the temp was as opposed to what the thermostat had and it was perfect. It is small in size like maybe 3×3 in size. But effective

  45. Dj

    Easy to use

  46. George

    Have one in the freezer, another in the refrigerator, one on the back deck and one inside for room temp. Monitor them all my iPhone. Sends me a message if my freezer or fridge quits working.

  47. Mandy

    The Bluetooth humidity and temperature monitor works well. The package comes with instructions and directs you to download the ThermoPro app. The app is why I give this product a two stars review. I have no issue connecting the device to my phone. The display looks nice. The issue I have is the app refuses to sync if I don’t have location turns on. I don’t mind if it needs location information to setup, but I do mind when the app needs location information every single time I open the app even though I have Bluetooth on. I plan to continue to use the device, but I will not sync it. Please check out the ThermoPro app reviews in the app store. It highlights other issues with the app.

  48. Tom

    This thermometer comes with a built-in magnet which makes it super easy to stick to my metal work cabinets. I keep this jewel in the garage because it gets really hot where I live. The thermometer comes with instructions and a barcode that you take a picture of and Wala, it starts connecting to my Bluetooth phone. Works great, looks good, super easy !!

  49. Olddoc

    It blows my mind that this bluetooth-connected instrument with humidity and temperature sensors can be produced and delivered at a profit! It’s difficult to verify the accuracy of a hygrometer, but my unit tracks my HVAC sensor closely. My 4 star rating, rather than 5 star, is because I received no instructions. A web-site was listed (without comment) so I was able to download the iPhone app and learn how to enable bluetooth connectivity.

  50. Thomas mcnaught


  51. Larry Bosch

    Great product and price

  52. Jerry Kerll

    I have two of these for my camper van. One on the inside, one outside. So, for $20, using the free and awesome app, I effectively have a very reliable and easy to use temperature- sensing system that also keeps records of past temps. Also, the company is great – I had an issue with one of the thermopros and they responded quickly and courteously and helped me the resolve the problem by making use of their excellent warranty. I highly recommend this product and this company!

  53. Clayton L. Barnes

    The thermometer works great and seems to be very accurate. I would have given this 5 stars but the ThermoPro Sensor app is not the greatest. It is nice to be able to see temperature and humidity fluctuations in graph form, but I was really hoping the app would send me a notification when the temperature/humidity reached undesirable levels. It will send a notification, but only while the app is open and being used, which is kind of silly. This is not a phone setting issue, as I have looked into and tried to problem solve on that front. This is an issue with the app. Other than that, great thermometer!

  54. Joey NYC

    my freezer the defrost cycle had become intermittent, and i need a way to monitor it till i could depend on it working reliably. long story short, it turned out to be an internal electrical connection that needed tightening after years of metal fatigue and oxidation, but the point of this review is to report how this device behaves in a subzero application. i simply magnet stuck this meter to the inner rear metal plate where the defrost heater resides, so every time it cycled hot i would notice a brief but major temperature rise (see graph).i can report that well below freezing this meter does something odd.. the humidity eventually jumps by 20% so even though my freezer humidity was actually under 30% the meter showed it around 50%, so it’s likely this meter is not at all suitable for outdoor applications either. to protect the air exposed circuitry while in the freezer, i covered all the vents on the plastic casing with a layer of masking tape, since the spot i needed to record was near a fan vent – this worked fine without compromising the meter.i’m happy to report that despite a freezer being a form of faraday box, the bluetooth signal this meter put out managed to penetrate the sheet metal and reach my line of sight cellphone from 20′ away. the fact that the meter also appears to put out a battery status meter is handy to know. i do wish the app was a bit more intelligent, so we could auto check the meter at designated intervals even while our phone is sleeping and set high low alarm thresholds, but for what i paid here, i’m just glad it was able to retain enough recorded history to be useful between bluetooth connected uploads between the meter to my phone.

  55. Marina

    They work great, and connectivity is good too. You can also check the history which is very very nice!

  56. schrade badger

    Bought one of these just over a week ago and liked how it worked. Was going to buy a second one. To my surprise the cost had gone up dramatically. Guess I won’t be buying anymore.

  57. Catherine Jo Morgan

    Updated review: Tried updating the sensor placed in another building 60 feet away, putting the phone close to the door. Then just left it alone for a while. When I checked it again it had updated just fine. Don’t know how long this took, but it did work. So for the price, I recommend the pair.

  58. Amazon Customer

    Like everything

  59. Krishia Shante’ B. Sevilla

    Product works great. I am not sure if it is an accurate reading since I don’t have anything to compare it to. The battery it comes with seems to be lasting so far. We have had it for a week and set up in our babes room (8-month old). Her room is the coldest (during the winter) and warmest (during the summer) room in the house. So I needed a way to monitor the temperature so she doesn’t freeze and/or overheat. Easy set up, small and doesn’t take up much space, we have not have a problem with connectivity since installed, and seller was responsive when I had a question regarding the notification settings.We are returning this item because of the notification settings on it. So, you are able to set the notifications to notify you when the temperature and humidity is too high or low. Which is great, exactly what we were looking for. You can rename your device on the app, but good luck getting the name to save – never worked for us (not a huge ice breaker). Another, down side which doesn’t make any sense what so ever, the notifications only go off once you open up the app and it refreshes/reloads. So you have to constantly open up the app to check or you have to keep your phone on and app open and pull down to refresh it. Only then will the notifications go off. Not exactly what you would expect when you enable notifications for a device. I contacted the seller to ensure I wasn’t missing anything with set up and they did in fact confirm – notification only pop up once app is open.If it notified me without the app actually being open we would’ve kept it. Unfortunately, it does not work for our needs.

  60. Rag Picker

    I bought a 3-pack of these to keep track of the humidity in three of my rooms with Amish-made furniture. They seem to do the job and are small enough to fit anywhere. I haven’t used the blue tooth and I’ve had these for too short a time period to judge the battery life, but the price was reasonable and I am satisfied.

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TP357 Specification

Temperature Range -22.0 to 140.0℉(-30.0 to 60.0℃)
Temperature Tolerance ±0.5℉(±0.3℃) from 32 to 140℉(0 to 60℃) otherwise ±0.9℉(±0.5℃)
Humidity Range 10%~99%
Humidity Tolerance ±2% form 30% to 80%,otherwise ±3%
Sensor Type NTC
Refresh Rate 10 seconds
Transmission Range* 260ft(80m)
Wireless Technology Bluetooth 5.0
Display LCD, 1 11⁄16  Length x  1 7⁄32 Width inches (43L x 31W mm)
Backlight N
Unit Size 2 3⁄16 Length x 2 1⁄8 Width x 11⁄16 Height inches (55.5L x 54.0W x 17.5H mm)
Power 1.5V (1xAAA Battery)
*The stated transmission range is based on tests at an ambient temperature of 77°F or 25°C without any obstructions or electromagnetic interference. Your range can vary depending on the number of obstructions and electromagnetic in your environment.

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Price $12.99 $13.77 $8.99 $9.53 $12.99 $13.77 $15.99 $16.95
Availability In stock In stock In stock Out of stock
Alexa capability No No No No
Backlight display No No Yes Yes
Barometric pressure No No No No
Bluetooth Yes No No No
Calibration feature No No No No
Comfort indicator Yes Yes Yes Yes
High low records Yes No Yes Yes
Indoor outdoor Indoor Only Indoor Only Indoor Only Indoor Only
Mobile app Yes No No No
Range 260ft - - -
Remote Yes No No No
Temperature humidity alerts Yes No No No
Weather forecast No No No No
Wifi capability No No No No
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