10 Best Infrared Thermometers (Review) In 2021

Features To Look For In Infrared Thermometers

Infrared thermometers offer an array of different features so choosing the one that’s right for you can seem a bit confusing. In an effort to bring clarity to the process we’ve created this list of the most important features to look for in an infrared thermometer and why they’re important.

Temperature Range - Obviously you buy a thermometer in order to figure out the temperature of different things. So the effective range of the thermometer is important. Most of the best infrared thermometers on the market today have an effective range that starts well below zero (Fahrenheit) and extends upward past 1,000 degrees (again, Fahrenheit). Some designed for industrial purposes can measure even higher temperatures. Essentially if you are purchasing the contactless thermometer for home or automotive use you won’t need anything that measures the extreme ends of the temperature spectrum. So the standard range of about -58 to just over 1,000 degrees Fahrenheit should be more than sufficient.

Accuracy & Speed - One of the most impressive attributes of the digital infrared thermometer is their accuracy. Typically the thermometer will be accurate to within just a degree or so, unless you’re measuring the extreme low end of the temperature setting. In that case the margin of error may be up to about 3 degrees. In addition, a standard IR thermometer for domestic or light business use (as in a restaurant) will typically return an accurate reading in about .5 seconds. Which is more than fast enough for anyone, even those engaged in temperature sensitive manufacturing processes.

Emissivity - The emissivity of an object is its ability to emit thermal radiation from its surface. This is important if you are to get an accurate reading of the actual temperature of an object. Most of the best infrared thermometers allow you to adjust the device to account for the different emissivity levels of different materials. This way you can be sure you’re always getting an accurate reading.

DS Ratio - The DS ratio is the distance to spot ratio. It is a measurement of the size of the area to be measured relative to its distance from the measuring device (the thermometer). It often takes some time to get used to understanding the DS ratio but it’s not really that complicated. Within the DS ratio 1 equals the diameter of the area you are measuring. Whether that is 1 inch or 1 foot. While the larger number represents the multiple used to determine the maximum distance at which you can expect to get an accurate measurement.

So, if you intend to measure the temperature of an area that is 1 inch in diameter, and your infrared thermometer has a DS ratio of 10 to 1 then you can’t hold the thermometer more than 10 inches from the area you are measuring (1 inch x 10). Likewise if you are measuring an area that is 2 inches in diameter and your IR thermometer has a DS ratio of 20 to 1 then the furthest you can position the thermometer from the object would be 40 inches (2 inches x 20). And so on.

Types Оf Infrared Thermometers

There are 3 main types of infrared thermometers on the market today. They are:

• Spot infrared thermometers - Most infrared thermometers sold for home or light commercial use are some type of spot thermometer. These measure the temperature of a specific spot on a given surface. Whether that’s the surface of your roast, or your car radiator, or your arm or the coffee pot.
• Infrared scanning systems - A scanning system is similar to a spot thermometer except that it does not confine itself to a specific spot on a surface. Instead, it will scan a large portion of a surface in order to determine the average temperature of that surface. In most cases you’ll only find these in factories where it’s necessary to keep track of the temperature of various materials in order to ensure the quality of the finished product.
• Infrared thermal imaging cameras - Formerly the exclusive domain of the military or NASA, thermal imaging has found its way to the home and the toolbox of the average electrician. They’re no longer strictly big picture devices that can tell us something about distant galaxies or enemy encampments in the distant hills. Today’s thermal imaging cameras are palm sized dynamos that will tell you if your pizza is evenly cooked, or if the person standing on the dark on your porch is friend or foe.

Uses Оf Infrared Thermometers

Infrared thermometers have a wide range of applications and are often used by:

• Auto mechanics - Auto mechanics use the IR thermometer to assess the state of a car’s cooling system, to diagnose whether a car is overheating and what might be the cause, to find the cause of misfiring and to check the state of disc brakes, ball bearings and air conditioning systems.
• Manufacturers - IR thermometers are often used in factories to keep an eye on various manufacturing processes. They’re also used to diagnose the state of machinery and to determine whether certain ingredients (whether organic or inorganic) used in various processes are at the right temperature.
• HVAC technicians - Heating Ventilation and Air Conditioning technicians use laser temperature sensors to determine the location of leaks in the system, to assess potential insulation issues, to identify possible electrical faults and to determine the temperature of various pipes, ducts and assorted substrates.
• Chefs - Professional chefs often use this type of thermometer to make sure various foodstuffs are at a safe temperature. This helps prevent the proliferation of contaminants and ensures any dishes served to the public are safe to eat.
• Electricians - Electricians need IR thermometers to diagnose a range of potential problems, identify electrical hotspots, prevent various types of equipment from overheating and ensure a balance of electrical power within a given system.
• Parents and medical professionals - Infrared thermometers are used by medical professionals to quickly and accurately assess a patient’s body temperature in a non-invasive way. Parents also use them to assess the state of their children if they seem ill or otherwise out-of-sorts.
• Homeowners - Homeowners have found that having a digital infrared thermometer at the ready can be useful for cooking, checking for leaks in the air conditioning or heating system, baking and even demonstrating to kids why they shouldn’t touch the oven door, coffee maker or toaster.

Infrared Thermometer FAQ

Q: What is an infrared thermometer?

A: Sometimes called a laser temperature gun or contactless thermometer this is a device that measures the thermal radiation that different objects emit. Nearly every object and being on earth emits some type of infrared radiation and this is what the IR thermometer picks up on. Most of the best IR thermometers are able to calculate the emissivity of different objects as well. Emissivity is the amount of thermal energy different materials are capable of emitting. Some hold onto more IR radiation than others. So, you simply enter the emissivity of the object or the material you want to take the temperature of into the IR thermometer, then point it at the object, pull the trigger and it returns an accurate temperature.

Q: How to use an Infrared Thermometer?

A: To use a spot thermometer power up the unit and then give it a moment to run through its self-diagnostic programming. Then select whether you want to measure in Fahrenheit or Celsius. Keep in mind the DS ratio as explained above and make sure you don’t try and obtain a temperature by exceeding the recommended distance between the object and the thermometer. In most cases you don’t want to try measuring from the longest allowable distance. You want to get as close as possible. Sometimes, however, the heat from the object will make it impossible to get very close so don’t hurt yourself. Pull back to the max distance allowable to get your reading. It will still be accurate to within a degree or so.

Q: Are infrared thermometers accurate?

A: Yes. The best infrared thermometers are highly accurate. And the closer you are to the object whose temperature you want to measure the more accurate the reading will be. But even if you have to pull back to the maximum allowable distance you’ll still get a highly accurate reading. When purchasing an infrared laser thermometer keep in mind the kind of objects you intend to use it on. If they tend to be extremely hot you’ll want to make sure the IR thermometer will allow you to measure them from a safe distance.