A Doctor Ranks The Most Accurate Ways To Take Your Child's Temperature

Any time my kids have been sick, taking their temperature has felt like a particularly onerous task. It just seems like I never really know what’s the best way to go about it, and I always second guess whether my thermometer is working or if I’ve just screwed it up somehow. TikTok creator Dr. Mona (@pedsdoctalk) feels my pain, noting that thermometers “can sometimes feel more like fortune tellers than actual science tools.” So she took the time to break down her preferred methods — in order — and then we’ve taken the time to tell you the best way to do them.

#1 Rectal (Butt)

Dr. Mona refers to this as the “gold standard” of temperature checks, which makes sense because it’s being taken from inside the body. However, the problem here is that it’s really only going to be effective for children under 2 since children over the age of 2 likely will not be down for it.

Method

To take an accurate rectal temperature, wash the end of a digital thermometer with soap and water and rinse. You can also use single-use plastic “probe covers” as well. Moisten the tip of the thermometer with a lubricant like petroleum jelly or Aquafor. Either place your child belly-down on your lap or on a flat surface, with your hand on their back or face-up with their legs up and your hand against the back of their legs (think “diaper change” position).

Next, insert the thermometer between half and one inch into the anus. Gently but firmly cup their bottom, steadying the thermometer between your middle and index fingers. Once the thermometer beeps you’ll have an accurate temperature reading.

If your baby’s been in the bath or under a lot of blankets or layers of clothing, wait 20 to 30 minutes before taking their temperature, otherwise you might not get a true reading.

Only use this thermometer for rectal use. Write “Rectal” on the thermometer itself in permanent marker so there’s no mistaking it.

#2 Oral (Mouth)

Again, because this is a temperature taken from inside the body, this will be pretty accurate as well, but there’s a caveat. Dr. Mona warns that this should only be done with children 4 and older, since children younger than that won’t really be able to keep the thermometer under their tongue, which is crucial for accuracy.

Method

Using a digital thermometer, place the tip of the thermometer under your child’s tongue and tell them to close their lips around it. Tell them not to bite down on the thermometer or open their mouths. Once the thermometer beeps you’ll have your reading.

Ideally, ensure that your child hasn’t eaten or drunk anything within 20 to 30 minutes before taking their temperature orally. The temperature of their food and drink could affect the reading. Make sure there’s no gum or candy in their mouths.

#3 Tympanic (Ear)

Some of us are old enough to remember when these thermometers came on the scene, and they felt like a game changer, working by reading infrared heat waves from the eardrum. Dr. Mona, however, has some reservations. “[Ear thermometers are] great in theory, tricky in execution,” she warns. “Did you angle it right? Did it even get a clear path to the ear drum, or is it just chilling in ear wax territory?”

Here’s how you can get the best measurement possible via your kiddo’s ear.

Method

Because each of these types of thermometers is going to be slightly different, it’s important to read the instructions that come with it. In general, though, you’re going to want to pull the ear back and up in order to access a path to the eardrum. Aim the ear probe between the opposite eye and ear. Once it beeps you’re all set.

Tympanic temperature checks aren’t recommended for babies six months and younger as their ear canals are too narrow to reliably allow access to the eardrum. If your child has been out in the cold, that can affect the reading, so wait until they’ve been inside for at least 15 minutes.

#4 Temporal (Forehead)

You might think that this method works by measuring skin temperature. Not really. This measures temperature from the temporal artery located on the side of the forehead just above the temple. That said, it’s very easy for these thermometers to pick up on your child’s skin temperature, which can make the reading less accurate.

“Let’s be real,” says Dr. Mona, “kids are professional furnace imitators.”

Method

Again, you’re going to want to read instructions for your particular thermometer. Generally, however, you should place the sensor in the middle of the forehead and, maintaining contact with the skin, drag across the forehead to the temple, following the hairline, if applicable. When the thermometer beeps or clicks you have a reading.

Axillary (Armpit)

This is the least accurate way to measure temperature, as it just measures skin temperature, but if you don’t have specialized thermometers and your child won’t consent to a rectal temperature and isn’t old enough to get an accurate oral temperature, this might just be your best bet.

Method

Removing your child’s shirt, hold a digital thermometer against the skin of their armpit and fold their arm across their chest to keep the thermometer in place. Avoid taking their temperature after a hot or cool bath or after they’ve been bundled up under blankets or layers of clothing. Once the thermometer beeps you’ll have your reading

But at the end of the day...

Dr. Mona wants parents to know it’s less about exact temperature and more about a child’s behavior. If they’re drinking, sleeping soundly, breathing comfortably, and playing (even a little), they’re probably OK.

“A kid happily arguing about snack choices with a fever? That’s vibe-based parenting success,” she says. “Treat the child, not the number.”