What to Know About Infrared Thermometers for Children

Medically Reviewed by Amita Shroff, MD on July 30, 2023
3 min read

There are many types of thermometers available for temperature readings. An accurate temperature reading is important for newborns and infants. A small temperature change can make a big difference. Research shows infrared thermometers are as accurate as other thermometers while being less invasive. 

A no-touch forehead thermometer uses an infrared scanner to read the temporal artery temperature on your forehead. This type of thermometer takes your temperature quickly and accurately. You don’t have to wait for an underarm reading or put anything in your mouth or ear. Infrared thermometers can be used on a person of any age, including newborns. 

Infrared thermometers for children are often more expensive than other thermometers. They may also be less accurate depending on the surrounding conditions. Things that may impact an infrared reading include: 

  • Direct sunlight
  • Colder surroundings‌
  • Sweaty forehead

It’s also possible to hold the scanner too far away from your forehead. While it is meant to be a touchless solution, infrared thermometer effectiveness depends on the device being held close to your skin for an accurate reading.

Infrared thermometers for newborns and infants. No matter what type of thermometer you use, taking a newborn or infant’s temperature is different than taking an adult’s. This is especially true for newborns who can experience life-threatening symptoms with a high fever.

Infrared thermometers are also a great option for young children. It means they don't need to sit still for a long period of time for you to get an accurate reading. It may also reduce your child’s anxiety over having a thermometer put into their ears or mouth.

If you want other options besides an infrared thermometer, try one that reads temperatures using a different body part:

  • An oral thermometer is placed under your tongue.
  • A rectal thermometer is inserted into your anus and is often considered the most accurate.
  • An axillary thermometer reads your temperature from your armpit‌.
  • A tympanic thermometer reads your temperature in your ear.

Rectal or axillary readings were once the preferred options for an accurate temperature reading because a slight difference may be dangerous. But studies now show that an infrared thermometer is just as accurate for taking a newborn’s temperature. Over a seven-day study of newborns, there was not a notable difference between infrared and axillary temperature readings.

The accuracy of temperature readings varies by the type of thermometer you use. You may have to adjust the reading up or down based on which reading you take. While there is not an exact scientific link, medical professionals generally agree that:

  • An oral temperature is a normal reading around 98.6 degrees Fahrenheit.
  • A rectal reading ranges from 0.5-1 degrees Fahrenheit higher than an oral reading.
  • A tympanic reading ranges 0.5-1 degrees Fahrenheit higher than an oral reading.
  • An axillary reading ranges 0.5-1 degrees Fahrenheit lower than an oral reading.‌
  • A temporal reading ranges 0.5-1 degrees Fahrenheit lower than an oral reading.‌

Use this guideline to add or subtract a single degree based on the type of thermometer you use. For example, if you have a three-year-old and use an infrared thermometer, you may have a reading of 100 degrees Fahrenheit. The rectal or tympanic reading is probably closer to 101 degrees Fahrenheit.

Instructions. Each type and brand of thermometer is different. Even if you’ve used an infrared thermometer before, read the instructions for a new one carefully. Learn how to store and maintain your thermometer for the most accurate readings over the life of your thermometer.‌

Remember that body temperature is different for adults and infants. No matter your age, 100.4 degrees Fahrenheit is the threshold for a fever. But a higher than normal temperature is much more alarming in a newborn or infant than in an adult. 

Consider the time of day when you’re taking your temperature. In the morning, your temperature is naturally lower. It’s higher in the afternoon or evening after a day of activity. Your diet and exercise may also impact a temperature reading in some cases.‌

A fever is usually a sign of an infection or illness. You may perceive a fever is a bad thing because of how you or your child feel, but it’s a sign your body is fighting off bacteria or a virus. ‌

Aside from an infection, other causes of a fever include:

  • A chronic health condition, like juvenile rheumatoid arthritis, that leads to inflammation
  • Short-term reactions to a drug or vaccine‌
  • Some cancers