A thermometer is a portable medical device that measures body temperature.
A thermometer is an essential component of any home first aid or emergency kit and provides a fast, reliable measure of a person’s overall health.
Mercury-filled, glass thermometers are no longer advised for home use. In their place, we have high-tech digital thermometers that provide fast, accurate readings with none of the health hazards associated with mercury. Below are the best thermometers of 2021.
Rankings
1. BLScode Infrared Thermometer
Click here for the lowest price on Amazon
The BLScode Infrared Thermometer is light, fast, and accurate, has a nice clear display, and does not require contact with the person being checked. Perfect for families or businesses monitoring the temperature of patrons as they enter.
What we like: You get a precise reading in about a second without having to make contact. That way you can monitor your child’s temp while they sleep. It saves the last 10 entries and switches between F and C in a snap.
Flaws: Batteries not included.
2. GoodBaby Thermometer for Kids and Adults
Click here for the lowest price on Amazon
The most important aspect of any thermometer is the reliability of the data it presents. The GoodBaby Thermometer for Kids and Adults has a sparkling record of providing accurate information. It is also affordable and built to last.
What we like: The name is GoodBaby, but it works just fine on everyone in the house. It stores the 35 most recent readings so you can identify trends. Can be used either on the forehead or in the ear.
Flaws: It tends to drain the batteries pretty quick. So have extras on hand.
3. Sanpu Digital Oral Thermometer
Click here for the lowest price on Amazon
Taking your child’s temperature should not be a complicated matter. Sanpu provides you a simple, proven way to obtain an accurate temperature reading from your child or yourself. Their thermometer is easy to use and remarkably affordable.
What we like: The device is compact and easy to carry. It has a low instance of faulty readings. There is an alarm that signals a worrisome temperature. And it can be used in multiple ways depending on your needs.
Flaws: Takes up to a minute to deliver the temperature.
4. Withings Thermo
Click here for the lowest price on Amazon
Who knew style and healthcare could co-exist? Withings apparently did. Their Thermo is a fusion of leading-edge design and peerless high-technology. Non-contact thermometers have never looked so good.
What we like: We love the sleek, slick design. The device uses 16 infrared sensors to gather an accurate temperature profile. That temperature is displayed quickly and is visible in the darkest room.
Flaws: The app is fairly useless. And the device will not work unless you jump through all the setup hoops.
5. Chooseen Forehead and Ear Thermometer
Click here for the lowest price on Amazon
Chooseen has upgraded their Forehead and Ear Thermometer and made it more reliable and easier to use than ever. This is a versatile, reliable, affordable thermometer that produces accurate measurements in Celsius or Fahrenheit in about a second.
What we like: The device can store up to 35 recent temperature measurements so you can spot trends. It is easy to switch back and forth between Celsius and Fahrenheit. Measurement displays in 1 second.
Flaws: Can be temperamental.
6. Braun Thermoscan 7 IRT6520
Click here for the lowest price on Amazon
There is no arguing with the Braun build quality. Their Thermoscan 7 is beautifully engineered, accurate, and reliable. It is also blissfully simple in execution and comes with 40 lens covers to ensure proper hygiene.
What we like: The device is reliable, easy to use, and returns a temperature in just 1 second. The tip of the device warms up, making it more agreeable for kids. If it detects a fever the screen will turn red.
Flaws: For the price, we really wanted more versatility.
7. Korier Digital Basal Body Thermometer
Click here for the lowest price on Amazon
Sometimes you do not want to be bowled over by high-tech extras. You just want a fast, accurate temperature reading. That is exactly what you will get with the Korier Digital Basal Thermometer.
What we like: There are no distracting bells and whistles. Readings are (relatively) fast and accurate. The device is very compact and easy to take with you wherever you go. Also has a useful fever alert and money-back guarantee.
Flaws: Takes a full minute to produce a reading.
8. iHealth No-Touch Forehead Thermometer
Click here for the lowest price on Amazon
Non-contact thermometers are the safest way to obtain the information you need without the risk of spreading germs among family members. The iHealth No-Touch is a style winner that provides fast, accurate readings in a non-invasive way.
What we like: Collects temperature data from more than 100 points on the forehead. The device vibrates gently when the reading is ready. Overall accuracy is very high. It can be used by anyone in the family.
Flaws: Battery powered, so make sure you always have batteries on hand in case you need them.
9. Braun No-Touch + Forehead
Click here for the lowest price on Amazon
Non-contact thermometers like this are the safest ones to use on multiple family members. Once you have the Braun No-Touch + Forehead set up, it will provide highly accurate temperature readings time after time without spreading germs.
What we like: A very simple device that does not require contact. Temp is displayed quickly. The display screen is backlit for dark rooms. And you can silence any alarms so you do not wake up your child while you take their temperature.
Flaws: Requires you pay close attention to the settings to get an accurate reading.
10. TrackAid Medical Forehead and Ear Thermometer
Click here for the lowest price on Amazon
This TrackAid thermometer provides you with a highly accurate reading in as little as a second. It is well-built, easy to read, and comes with a handy travel pouch because good health is not guaranteed when you travel.
What we like: Switches easily from forehead to ear mode and back. Keeps a log of the past 20 readings so you can keep track of temperature trends. Returns the temperature in about a second.
Flaws: You have to be diligent and take the temp exactly the same way every time or you risk inconsistent readings.
Who Needs a Thermometer?
Pretty much everyone could benefit from having a reliable thermometer on hand in the home. A thermometer is essential frontline healthcare equipment that provides important information regarding the state of you or your loved one’s health at any given time. In this age of heightened awareness of viral threats, having a thermometer in the house is simple common sense.
Oftentimes the first indication of an emerging health problem is a fever (1). Exactly why people’s body temperature rises when they get sick is not entirely clear. A popular theory is that the body raises its temperature to kill off any temperature-sensitive invaders that may be present (2). But not everyone is on board with that explanation. But regardless of why temperatures happen, they are nonetheless a clear indicator that something is not right.
How We Ranked
While today’s high tech digital thermometers often come with impressive-looking displays and lots of buttons and switches, the fact is they have one overriding purpose: to provide an accurate reading of a person’s temperature. If they do not do that, then the bells and whistles are meaningless. So accuracy and consistency were the primary determining factors in whether or not a thermometer ranked for our list.
Other things we considered included the quality of the display. Was it easy to read even in a darkened room? Or was it poorly lit and cluttered with superfluous and confusing information and graphics? Some thermometers also provide helpful warning alarms that sound if the reading exceeds a specific temperature. This can alert you to a potentially dangerous situation. Also, did the thermometer store previous readings that could be retrieved so that you can determine temperature trends?
Finally, smart add-ons were nice, but apps in this case are more curiosity than necessity. So, if a given thermometer did not have an app, or was not able to sync with a smartphone, it did not suffer in our rankings. We also endeavored to provide a range of price options for our readers. Because not everyone has $200 to spend on a thermometer.
Benefits
Note: While a limited number of mercury thermometers are still available, they are no longer advised for home use. Therefore, the benefits listed below are the benefits of the digital thermometer.
A thermometer gives you an accurate picture of your condition. Today’s digital thermometers are not just fast and convenient, they are typically more accurate than yesterday’s mercury thermometers. Today’s thermometers can give you a precise temperature right down to the tenth of a degree and present that to you on a large, easy to read digital display. That way, you can make your next decision based on sound information.
A thermometer can give you a quick idea if something is wrong. Infrared thermometers will often provide an accurate reading in a matter of seconds. If you are concerned that your child may be coming down with something, being able to obtain their temperature quickly can enable you to switch to treatment mode without delay.
A thermometer is more important than ever now. The coronavirus outbreak (3) has sent shockwaves through communities worldwide and caused unprecedented disruption. Millions fear they or their loved ones may be the next to fall victim. Early recognition of the symptoms and aggressive treatment is crucial to a positive outcome. A thermometer can provide you with that early warning.
A thermometer lets you choose where to take the temperature. Depending on the type of digital thermometer, you may be able to use it in the mouth, the armpit, or the rectum. Other thermometers give you a choice of obtaining a temperature via the forehead or ears. The point is, you are rarely confined to only one way to get the temperature reading you need.
A thermometer does not have to touch someone to work. Infrared thermometers do not have to touch a person to read their temperature. This can be a major plus if you have a sick child who is uncomfortable and having a hard time sitting still. You can take their temperature quickly in a painless, non-invasive way.
A thermometer is an essential part of any home first aid kit. Every home should have an emergency first aid kit. If you do not currently have one, you should put one together simply because you never know when you might need it. And that is true whether you live alone or have a large family. A thermometer is considered by all major health organizations to be an essential component of any home first aid kit (4).
A thermometer can provide a temperature history. Knowing your temperature or the temperature of a loved one is important. But if someone is sick, it is also important to be able to track their temperature history. This can indicate whether they are still in danger or are on the mend. Most of the best thermometers today provide a temperature history. Some go back as many as 20 readings.
A thermometer is safer than traditional thermometers. Mercury thermometers have fallen out of favor for numerous reasons. None more so than the fact that they are dangerous. The whole notion of putting a stick of glass filled with mercury into a child’s mouth today seems ludicrous. And it is. Especially when there are so many easy to use, accurate and affordable digital thermometers available.
A thermometer provides peace of mind. Just as important to most parents as knowing their child is sick is knowing they are not sick. Suspecting your child may be ill, but not being able to prove it one way or the other leaves you in a terrible kind of limbo. It may be a long way to the doctor’s office, or it may be the middle of the night. Either way, being able to confirm that your child is okay can provide invaluable peace of mind.
A thermometer is easy to read. Traditional mercury thermometers are notoriously difficult to read. It often takes a lot of practice and experience to read them accurately, especially in low light. Today’s thermometers provide a large, easy to read digital display that lights up so it can be easily seen regardless of the light conditions. No more wondering if you read the thermometer correctly.
A thermometer can protect your family in uncertain times. Extraordinary times call for extraordinary measures. If you are having guests, over a thermometer can help ensure that your friendly post-lockdown get together is as safe as possible. After all, if it is good enough for stores, mass transit lines, and airports (5)(6), it’s good enough for your loved ones.
A thermometer can tell you if you need to call in sick. People sometimes wake up in the morning not feeling right. Still, they are unsure if they are just tired or if they need to call in sick. Having a thermometer at the ready can remove any doubt. You will know in an instant if you should call the office or head for the shower.
A thermometer is hygienic. Infrared thermometers obtain a temperature with having to contact the person. That is important during cold and flu season because it greatly reduces the risk of transmitting the cold or flu virus by way of the thermometer. You do not have to disinfect the thermometer every time you use it. Nor do you need to keep a separate thermometer for someone in the house who may be sick.
A thermometer requires very little maintenance. A digital thermometer depends on a lot of state-of-the-art technology to deliver its verdict. But, despite all the years of R&D that went into them, they are almost entirely maintenance-free. Yes, some will need to be recalibrated periodically. But that is done by the manufacturer, not you.
A thermometer is affordable healthcare. The price of staying healthy these days has gone through the roof. Fortunately, the digital thermometer is one component of your first aid kit that will not cost you an arm and a leg. Considering how long you are likely to have it, the actual cost will likely come to just pennies a day. When you think of how they can help you improve your overall health, that is money very well spent.
A thermometer has multiple uses. At least some of them do. Infrared thermometers, in particular, can be put to numerous uses. You can use them to see if a pot is too hot to handle, whether your coffee is still hot or whether your main dish has gone cold waiting for your guests to arrive. You can check the temperature of the baby’s bath and make sure that bowl you are about to retrieve from the microwave is not going to burn you.
A thermometer can provide readings in Celsius or Fahrenheit. Some people are more comfortable with Celsius (7), some are more comfortable with Fahrenheit (8). But whichever temperature scale floats your boat, most of today’s best thermometers can provide readings in both.
A thermometer has warning alarms. Old fashioned mercury thermometers were often so hard to read it was difficult to tell when someone was in the early stages of illness. Not so with today’s digital thermometers. Most of them are programmed to sound the alarm if they detect even modest temperature anomalies. It is the kind of early warning that can save a lot of trouble in the long run.
A thermometer can be used by everyone in the family. Trying to decide whether to use a mercury thermometer on a young child was almost as nerve-wracking as worrying whether they were sick. Most of today’s thermometers can safely be used by every member of the family, no matter how old or young.
FAQs
Q: What is a thermometer?
A: A thermometer (9) is a handheld device that measures body temperature. In the past, thermometers used glass-enclosed mercury which responded to heat and indicated the temperature on an analog scale. Mercury thermometers are no longer advised for home use, however. Instead, virtually all thermometers sold today are electronic devices that use infrared and other heat detection technology and display the temperature on a digital screen.
Q: Why do I need a thermometer?
A: You need a thermometer because it is not always possible (or necessary) to visit a doctor if you are feeling a bit under the weather. You need a thermometer because if your child is showing signs of illness, you need as much relevant information as quickly as possible so you can make informed decisions going forward. You need a thermometer because, with the world reeling from the coronavirus, you cannot be too careful.
Q: What is normal body temperature?
A: Two centuries ago, a German doctor named Carl Wunderlich (10) proposed that the normal human body temperature was 98.6 degrees Fahrenheit. That number stood as the ideal until just recently, when more widespread sampling revealed that the actual mean human temperature is more like 98.2 Fahrenheit. Depending on the individual, anything from 97 to 99 Fahrenheit is now considered normal (11).
Q: Do thermometers come with batteries?
A: Modern thermometers are safer and generally more accurate than old-fashioned mercury thermometers. If they have a drawback, it is that many are powered by disposable batteries. With some thermometers, a set of batteries is included. But with others, you will need to supply your own. Also, you need to make sure you always have extra batteries on hand, just in case.
Q: What are the benefits of an ear thermometer?
A: Some healthcare professionals are convinced that the ear is the best place to obtain a reliable body core temperature. This alleged reliability is the primary benefit of using an ear thermometer. Others, however, believe the ear to be an unreliable source of measurement because not everyone’s ear canal is the same size or shape (12). And both can affect temperature readings.
Q: Are there advantages to using a forehead thermometer?
A: First off, there are two kinds of thermometers that obtain temperatures via the forehead. Both use infrared technology to achieve their measurements, but one does not require contact with the skin, and the other does. In either case, an infrared thermometer is a fast and easy way to take a child’s temperature. Particularly one who is not feeling well and may be unwilling to sit still.
Q: What kind of thermometer is best for kids?
A: There is no single type of thermometer that can be said to be best for all children. The best type for your child will depend on a number of factors. Some children are less active than others. And some are less likely to react in an extreme way to discomfort. For these children, a digital stick thermometer may suffice. For restless children or those with lower discomfort levels, a non-contact infrared thermometer will be a better choice.
Q: What’s wrong with a traditional thermometer?
A: From a purely technical standpoint, there is nothing wrong with a traditional glass thermometer. The problem is that they use mercury (13) to indicate the temperature, and mercury just happens to be poisonous. Biting down on such a thermometer can produce catastrophic results because the person may swallow both glass and mercury. You can still buy mercury thermometers, but their use is almost universally discouraged.
Q: How do I clean a digital thermometer?
A: Any thermometer that is inserted into the oral, anal, or ear cavity to obtain a temperature reading will need to be cleaned after every use. In most cases, that entails wiping it down thoroughly with an alcohol swab. A cotton swab dipped in isopropyl alcohol may also suffice, as long as the tip of the thermometer is wiped down completely. Just make sure the tip is facing downward so that no alcohol can penetrate the interior of the thermometer.
Q: Can a microwave affect the accuracy of a digital thermometer?
A: This may seem like an odd question, but it is not. A microwave oven produces electromagnetic, or EM, radiation (14) that can interfere with the functioning of a digital thermometer. So, yes, a microwave oven is capable of affecting the accuracy of a digital thermometer. As such, you should not use a digital thermometer near a microwave oven while it too is in use.
Q: Can I take a thermometer out of storage and use it right away?
A: It depends on whether there is a difference in temperature between where the thermometer was stored and where you plan to use it. If there is, then you will need to let the thermometer sit in the environment where you plan to use it for up to 30 minutes before taking anyone’s temperature with it.
Q: What could be causing my inaccurate readings?
A: It could be that the thermometer was not given adequate time to adjust to the new ambient temperature after being taken out of storage. Or it could be that you touched the heat probe with your fingers. Also, blowing on the heat probe can throw off the measurement. And, if you use the thermometer while talking on your mobile phone, that too may interfere with getting an accurate reading.
Q: Is there any time when I shouldn’t take my temperature?
A: You should not take your temperature using an oral thermometer if you just finished eating, drinking, or exercising. That is because those activities can raise the temperature in your mouth (15) by a couple of degrees. In such cases, you should wait half an hour before attempting to take your temperature. The same goes for anyone else whose temperature you plan on taking.
Q: Is it safe to put a thermometer into a child’s ear?
A: Yes, given that it was designed for that purpose, of course. Not all digital thermometers are. You should not, under any circumstances, put a standard stick thermometer designed for oral or rectal use anywhere near a child’s ear. Also, even if a given thermometer is designed to be used in the ear, extreme care should be taken not to force the device into the child’s ear past the point of resistance.
Q: I dropped my thermometer. Will it still work?
A: Modern digital thermometers are packed with sensitive electronics vital to their proper functioning. Unfortunately, most are not impact resistant. That means that if dropped more than just a few inches onto a hard surface, there is a chance they will sustain damage. In some cases, an error message will appear on the display screen. In other cases, damage may manifest itself in less obvious ways.
Q: Can I use an ear thermometer if my child has an ear infection?
A: Ear infections (16) typically cause children a lot of pain and discomfort. Attempting to use an ear thermometer on a child suffering from an ear infection is not a good idea. If you have another way to obtain their temperature, such as an infrared non-contact thermometer, it is best to use that instead.
Q: Is there a right way to store a digital thermometer?
A: You should not store your thermometer in a place where the temperature is markedly different from the temperature where you might use it. If you do, you will not be able to use it immediately after taking it out of storage. That is because the thermometer will need to ‘acclimate’ to the new environment before it can provide an accurate reading. The reasons are complicated, but there is no getting around this fact.
Q: How often do you have to clean a digital thermometer?
A: If you are using a stick thermometer that is inserted into the mouth or rectum, you will need to clean it thoroughly with alcohol after every use. Same with an ear thermometer or a contact-based forehead thermometer. If, however, you have an infrared non-contact thermometer, it still needs to be cleaned, but not as often as a contact thermometer. Just be sure never to submerge your digital thermometer in water when cleaning it.
Related Articles
Recap
A thermometer is an essential component of any home first aid kit and an invaluable first line of defense against colds, flus, infections, and more. The modern digital thermometer is highly accurate, reliable, easy to use, and presents the temperature on a large, bright screen.
Thermometers take many shapes today, including digital stick, ear, and forehead thermometers that rely on bodily penetration to obtain a reading. And non-contact infrared thermometers that provide fast, accurate measurements without ever touching the person. Finally, classic mercury thermometers are still used by a small number of health professionals, but have fallen out of favor for home use.
Use the above information to make an informed decision regarding which thermometer will best suit your needs.
For cpoe.org’s #1 recommended thermometer, click here.