Whether for commercial use or just your household, your freezer needs to stay at 0° Fahrenheit (-18° Celsius) to maintain the quality of your food, so it stays fresh and flavorful for longer. Unfortunately, ensuring that happens isn’t as easy as setting the thermostat to the right temperature and walking away.
Power outages, equipment failures, and partially or improperly shut doors can lead to a freezer full of unsafe, damaged, and thawed goods. For restaurants, medical supply warehouses, and food processing plants, a temperature shift that goes unnoticed can be crippling and extremely costly.
A freezer alarm with remote monitoring functionality is the best way to ensure your household freezer or commercial walk-in cooler is operating at a stable and safe temperature.
The best freezer alarm systems come with a smartphone app and WiFi connectivity, allowing you to constantly monitor the temperature of your refrigerator or freezer from anywhere at any time. They will also send alerts directly to your smartphone if the temperature reaches dangerous levels so you can take preventative action before your food becomes spoiled and unsafe to consume.
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Best Freezer Alarm and Refrigerator Thermometer Reviews
To help you find the best freezer monitoring system for your home or commercial freezer, we’ve put together a list of the highest-rated freezer alarms on the market. Let’s get started.
1. Best Overall: Temp Stick WiFi Temperature & Humidity Sensor
Made in the USA, the Temp Stick is an accurate and reliable WiFi freezer alarm that will allow you to monitor your freezer’s temperature level from anywhere. The compact sensor runs on 2 AA batteries which provide a battery life of up to 12 months. Just make sure to install lithium batteries when you use the sensor in your fridge or freezer, as they last longer than alkaline batteries in extreme conditions.
There are no subscriptions fees or gateway devices required to get the Temp Stick connected. Simply power on the device and connect to the smartphone app, which is available for Android and iOS devices, and you’re ready to start monitoring. The whole setup process takes just three minutes.
The Temp Stick WiFi freezer alarm has a temperature range of -40°F to 140°F with an accuracy rating of ±0.4°C. The sensor is factory calibrated, and you’ll even be able to adjust the calibration if required. You can access all your data and settings through the intuitive app. You can view an unlimited history of readings, set your alerts for high and low temperatures, and monitor current conditions. You can also add an unlimited number of sensors to one account so you can monitor multiple cold storage areas simultaneously.
You can set the WiFi freezer thermometer to take readings every 60, 30, 15, 10, or 5 minutes. Unfortunately, as 5 minutes is the shortest interval, it is not a real-time reading. However, for most applications, a 5-minute reporting interval should be more than adequate. The longer intervals are in place to help extend the battery life.
If your freezer exceeds your custom alert’s temperature range, the WiFi freezer alarm will send a warning to your mobile device via text (SMS) or email, as well as up to ten other contacts of your choosing. We think it’s a very convenient feature to add co-workers or family members to the alert system. There’s also an alert if the sensor loses internet connection and when the batteries are low.
Based on our tests when we reviewed the Temp Stick, we found that the alerts came in without fail to our smartphone and the sensor’s accuracy is on par with one of our high-end weather station’s temperature sensors.
With the Temp Stick’s monitoring capabilities via WiFi, it will notify you immediately when a critical temperature change occurs no matter where you are. A WiFi freezer thermometer is the most versatile option to monitor the temperature of your refrigerator or freezer from just about anywhere, 24/7. Cellular freezer alarms require monthly subscription fees, while Bluetooth and standard wireless freezer alarms have a limited transmission range.
The WiFi freezer alarm also comes with a 3-year warranty, and if you do run into any issues while using or installing the sensor, you can quickly get help by reaching out to Temp Stick’s US-based team, who offer free email and phone support 7-days a week.
If you’re looking for a trustworthy and easy-to-use WiFi freezer alarm, the Temp Stick is our number one recommendation. It’s an affordable and reliable sensor that will get the job done without any hassle.
2. Runner-Up: MarCELL Pro Cellular Freezer Monitoring System
With an in-built cellular modem and pre-activated SIM card for data transfer, the MarCELL Pro Cellular Freezer Monitoring System is the best freezer alarm for homes or commercial spaces that lack WiFi. It does require a nearby electrical outlet, but the system will keep running and send alerts during power outages thanks to an internal backup battery.
Setting up the MarCELL Pro Cellular freezer alarm is easy, and you don’t need to sign any contracts to start enjoying the system’s many benefits. Just register for an account, then plug in the system, and you’re good to go. However, unlike the Temp Stick, you need to pay a monthly subscription fee for the cellular service. The service can be paid annually at a cheaper rate or month-to-month when required.
The freezer alarm comes with a detachable waterproof temperature probe that is 80 inches long with a temperature range of -20°F to 120°F. The highly accurate probe makes the MarCELL Pro ideal for use in a freezer or refrigerator. The MarCELL doesn’t just monitor the temperature. It can also monitor humidity, power status, and water leaks with the optional wireless Spuck sensors. We love that the MarCELL can monitor power status because if you do have a power outage, you will be immediately alerted so you can take action before the temperature inside your freezer rises to a dangerous level.
Customizable alerts are available via text, email, and even phone calls, and you can choose up to 9 people to receive the warnings. You can view all your readings via an easy-to-read dashboard after logging in to your online MarCELL account. The site is accessible via your computer or mobile, and it offers options to see real-time and historical data.
The freezer thermometer works by checking all conditions inside your cold storage space every 10 seconds, and it will alert you instantly if an alarm threshold is met. If everything is safe, it will not trigger an alert. Every half hour, this information is logged, and then the historical data is uploaded to the cloud every 8 hours so you can view it online. You’ll also receive 20 free “instant update” activations every month, allowing you to view your freezer’s conditions in real-time without waiting for the next automatic update.
The system comes with a 30-day money-back guarantee, 1-year warranty and it has been designed and manufactured in the USA.
If you don’t have reliable WiFi, the MarCELL Pro is an excellent option to monitor your freezer. The all-in-one cellular freezer monitor offers complete peace of mind.
3. Best for Home Use: Ambient Weather WS-8482-X3
If you need a fridge or freezer temperature alarm for use inside your home, we recommend the Ambient Weather WS-8482-X3. The unit offers smart home features, and it’s highly versatile as the device can connect to a range of different sensors that you can use for various applications around your property.
The WS-8482-X3 package includes three wireless thermo-hygrometer sensors and a display console with an internal sensor that measures temperature and humidity. You’ll also have the ability to connect four additional sensors to the console to monitor multiple appliances. Just make sure to position the console within range of the sensors.
The sensors connect to the console via a wireless radio frequency (915 MHz) with a 300ft line of sight range. However, the doors and walls of a freezer can limit the transmission range. The WS-8482-X3 also offers freezer monitoring via WiFi. The console connects to the Ambient Weather cloud platform, where you can view your data online through your smartphone or computer. You can also set alerts for high and low conditions on the cloud platform, and it will send those alerts out via text or email.
The Ambient Weather WS-8482-X3 isn’t quite as accurate as the Temp Stick. The wireless sensors on the Ambient Weather system have an accuracy rating of ±2°F. This level of accuracy might be okay for home use, but the Temp Stick will be a better solution for commercial applications.
If you’re looking to monitor the temperature and humidity in multiple locations around your home and not just your freezer or refrigerator, then the WS-8482-X3 is a top option. Adding sensors to the system is very affordable, and there’s also smart home support. You can connect to IFTTT to control other smart home devices, and it’s also compatible with Amazon Alexa and Google Home.
4. Best Budget Model: SensorPush HT.w Water-Resistant Wireless Thermometer
The SensorPush HT.w Water-Resistant Wireless Thermometer is a compact and accurate freezer alarm that is very affordable compared to other top wireless freezer thermometers. Despite its affordability, the unit provides reliable readings, and the water-resistant design makes the SensorPush an ideal choice for freezers.
Assembled in the US, the SensorPush HT.w is built with a Swiss-made sensing component. It has an accuracy rating of ±0.36°F and a temperature range of -40°F to 140°F. It’s good to go out of the box, but for even more accuracy, you can calibrate it to a trusted reference if required.
The SensorPush HT.w is a Bluetooth sensor that has a limited transmission range of 325 feet. Walls and other obstructions will reduce this, but many users successfully monitor walk-in coolers and freezers with the SensorPush HT.w. If you step out of the system’s Bluetooth range, you will lose connectivity, but the sensor will continue monitoring your freezer and store readings in its internal memory for up to 45 days. When your mobile device reconnects with the sensor, it will transfer all the collected data to your phone.
You can also connect to the SensorPush HT.w via WiFi. To do that, you have to purchase the optional SensorPush G1 WiFi Gateway. If you have the WiFi gateway device, you can monitor and control the SensorPush HT.w freezer thermometer from anywhere. However, adding an extra piece of hardware takes away from the compact and convenient nature of the device. It’s also expensive, and when you calculate the additional cost, the whole package becomes more expensive than our top recommendation, the Temp Stick, which has WiFi connectivity built-in.
Connecting to the sensor via Bluetooth or WiFi is easy. The mobile app is intuitive and user-friendly, and you can connect and monitor several sensors on it. Likewise, you can connect several mobile apps to one sensor, so everyone in your home or on your staff can keep an eye on your freezer’s performance. Data is taken down at one-minute intervals, and alerts are sent out instantly via push notifications. Unfortunately, text message alerts are not available.
The AcuRite 00515M is a basic freezer and refrigerator thermometer that is best suited for home users. It comes with two digital sensors—one for your fridge and another for your freezer. These thermometers wirelessly relay information to a digital display console that has a transmission range of 75 feet. The entire system runs on AA batteries and provides temperature updates every 60 seconds.
The refrigerator thermometer has a digital display with an easy-to-read LCD screen and a classy stainless-steel finish that will look good in any kitchen. Its magnetic backing allows you to mount the screen on your fridge. Otherwise, there is a keyhole for wall mounting and a foldout stand if you want to place it on your countertop. The unit’s wireless thermometers have multipurpose silicone straps that ensure hassle-free installation inside your fridge or freezer.
You can set the display to alert you with audible and visual alarms when your fridge drops below your selected temperature range. Unfortunately, the console can only store minimum and maximum temperature records limited to the past 24 hours. What you’re getting here is a capable refrigerator thermometer with a wide temperature range that offers the basics.
The AcuRite 00515M refrigerator thermometer is not WiFi compatible and can’t deliver alerts to your mobile device or computer. They only appear on the console. This aspect can create significant temperature monitoring gaps, as you’re unlikely to always be within earshot of the alarm. A WiFi freezer alarm like the Temp Stick may cost more upfront, but it doesn’t come with this concern.
The Brifit Refrigerator Thermometer is a wallet-friendly freezer alarm with two wireless sensors that send readings to an easy-to-read digital LCD console with a built-in sensor to measure indoor conditions. If you want a simple and affordable unit to quickly check the temperature of your fridge and freezer at home, then the Brifit refrigerator thermometer will be sufficient.
Each sensor requires two AA batteries, while the LCD screen includes a USB power adaptor. However, it does have battery-backup power. The magnetic backing on the console will allow you to position the display on your fridge door for optimal visibility. You can also mount it on a wall or use the stand to place it on a countertop.
The wireless sensors are easy to connect to the display, and once connected, you’ll be able to set your temperature alarms with a few button pushes. Like the AcuRite 00515M refrigerator thermometer, you only get the basics here. The Brifit refrigerator thermometer doesn’t have internet connectivity, and there are only standard memory functions that will show you each sensor’s minimum and maximum temperature records.
The Ambient Weather WS-10 is an ideal option to monitor multiple freezers or cold storage areas. It’s a highly affordable freezer alarm with three wireless thermometers and one display unit that also has an inbuilt sensor. You can connect up to eight thermometers to the display, including a thermometer with a waterproof temperature probe for freezer temperature monitoring. However, the wireless sensors need to be within 300 feet of the display console to work.
The display has a user-friendly interface, and the scroll feature automatically displays readings from each sensor every five seconds. The digital freezer thermometer will notify you with audible and visual alarms when your freezer’s temperature rises above or falls below your pre-set range. Unlike most freezer alarms, the remote sensors for the Ambient Weather WS-10 also have a convenient temperature readout.
The sensors each run on two AAA batteries, while the display requires four AAA. No batteries are included with the WS-10, so don’t forget to add that cost to your purchase price when comparing freezer alarms. The sensors operate with a temperature range of -40°F to 140°F, and they will update to the console at 60-second intervals.
Unfortunately, the WS-10 lacks internet connectivity and a companion app to monitor the temperature and store data remotely. However, this is a top digital freezer thermometer that packs a lot of value. It can accommodate up to eight affordable wireless sensors to help you monitor several cold storage locations at once.
Features to Look for When Buying a Wireless Freezer Alarm
Here are some essential features that you need to think about in order to purchase the best freezer alarm for your particular needs.
Accuracy and Temperature Range
Choose a wireless freezer alarm that has a wide temperature range but still provides accurate readings. The best freezer alarms on the market have a temperature range of around -40°F to 140°F and are accurate within less than half a degree.
Remote Monitoring Capabilities
Freezer alarms that only provide readings and alerts on a display console can increase the risk of your food being damaged as you won’t always be close to the console to hear an alert or monitor the temperature. Ideally, you should use a WiFi temperature sensor so you can check in with your freezer from anywhere via your phone. However, cellular connectivity is acceptable as well—if you don’t mind the monthly subscription fees.
As mentioned, it’s not enough for a freezer alarm’s display to beep and flash when your freezer’s temperature exceeds a safe range. Choose a system that can notify you, regardless of your location.
Freezer alarms like the Temp Stick and MarCELL Pro will notify you via text, email, and even phone calls. That way, you can quickly take preventive actions to stop your freezer’s contents from spoiling.
Before buying a freezer temperature monitoring alarm with wireless sensors, make sure that it has an extended transmission range. Since fridges and freezers have thick walls, you may have to place the display hub close to the appliance to increase the signal strength.
Battery-powered wireless freezer alarms are more portable and are typically easier to install than wired freezer alarms. We recommend using lithium batteries rather than alkaline batteries as they offer better performance and longevity in colder environments. It’s also helpful to choose a freezer alarm that displays battery levels and can alert you when the battery is low.
Look for a freezer temperature alarm that’s easy to set up and use. The display console, mobile, and web dashboard should be clutter-free and provide easy-to-read data. You should also have the option to see temperatures in your preferred format—Celsius or Fahrenheit. Freezer alarms with mobile apps are typically the easiest to use.
Additional Sensor Support
If you need to monitor multiple cold storage appliances or need to in the future, go for a freezer temperature monitoring alarm that can support multiple sensors.
Manually logging food temperatures can be tedious and inaccurate, but it’s a breeze with a freezer temperature monitor that logs and stores data online. Some freezer alarms will collect data logs several times a day and store an unlimited amount of data. You should also be able to access reports for specific dates to use them for assessments or other purposes.
Inconsistent or high temperatures can compromise the safety and quality of your food. An alert from a freezer alarm will help you take fast, preventative action before your products are damaged, saving you both time and money. A remote freezer alarm monitor will help you ensure that your freezer or refrigerator is working the way it should.
Overall, we recommend the US-made Temp Stick WiFi Sensor for commercial freezer monitoring and home users. It offers a straightforward setup, has WiFi connectivity built-in with zero subscription fees, and it’s highly accurate. Most importantly, the Temp Stick provides reliable alerts directly to your smartphone. If you don’t have access to WiFi, then consider the MarCELL Pro Cellular Freezer Monitor. It comes with a built-in cellular modem for remote freezer monitoring with instant notifications.