How to Check the Temperature of Your Baby


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If your baby shows signs of fever, it is essential for you to be aware of accurate ways in which you can check the baby’s temperature. Based on the reading on the thermometer you can decide on whether your baby needs to go to the paediatrician or not.

What is High Temperature in Babies?

In babies, 36.4 ºC or 97.5 ºF indicates a normal oral temperature, with slight variations. However, if the rectal temperature shoots up to 38 ºC or 100.4 º F, it may be an indication of fever, warranting a call or a visit to the baby’s paediatrician.

What Types Of Thermometers Are Used For Taking Baby’s Temperature?

Various types of digital thermometers are used to measure a baby’s temperature. These include:

  1. Multi-use digital thermometer: This thermometer uses metal strips with heat sensors which are connected to an LCD screen. A digital thermometer shows accurate reading up to the decimal points. This thermometer can be used to measure the oral, rectal and the axillary (armpit) temperature.
  2. Tympanic digital thermometer: This thermometer is used specifically for measuring the temperature of the ear canal. These thermometers read the infrared heat waves that are released by the eardrum.
  3. Temporal artery digital thermometer: It measures the infrared heat waves released by the temporal artery that lies right under the skin on the forehead. The shape of the thermometer allows it to be placed on the baby’s forehead with ease.

How to Check Baby’s Temperature Using Thermometers?

It is ideal to use a digital thermometer to check your baby’s temperature as it gives quick and accurate readings. If you’re using the thermometer for the first time, follow the instructions on the thermometer pack that has details on how to use a thermometer for babies. Do not immediately measure the baby’s temperature after a bath as it may give inaccurate readings. You will need to hold your baby in a comfortable position before placing any thermometer for accurate results and to reduce discomfort to the baby. Each type of digital thermometer has a different procedure that you need to follow.

How to Measure Rectal Temperature?

Measuring the rectal temperature is the best way to get an accurate reading in babies and toddlers up to the age of three. However, in cases where children older than three are unable to have their temperature measured orally due to a cough or congested nose, a rectal thermometer can be used.

Here’s how to measure the rectal temperature of your baby using a standard digital thermometer.

  1. Use a cotton ball dipped in alcohol to clean the thermometer and wipe it dry. You can apply lubricant or petroleum jelly to reduce discomfort while inserting the thermometer.
  2. Let the baby lie on his stomach as your partner holds him firmly. You can also lay the baby on his back and lift his legs up to his thighs.
  3. Spread the butt cheeks gently, enough to see the rectal opening clearly. Insert half an inch of the thermometer into the rectum. You can insert up to one inch for babies older than six months. Mark the thermometer before inserting so that you know how much to insert.
  4. Wait for two minutes with the thermometer in position until it beeps, or wait till the reading appears on the screen.
  5. Remove the thermometer gently and clean it with alcohol before putting it away.

The baby’s rectal temperature is normally 0.5 ºF (0.3 ºC) to 1 ºF (0.6 ºC) higher than normal oral temperature. If your baby’s rectal temperature is over 100.4 ºF or 38 ºC then he may have a fever.

How to Measure Temporal Artery (Forehead) Temperature?

Temporal artery thermometers are suitable for babies over three months of age. In babies younger than three months it can be preferred over axillary thermometers to be used as a screening device.

To use the temporal artery thermometer you need to,

  1. Hold the baby in a sitting position.
  2. Place the sensor end of the thermometer on the centre of the baby’s forehead and press the scan button. Gently swipe the thermometer across the forehead towards the hairline. Now release the scan button and record the temperature.

The normal temporal temperature in a baby is 0.5 ºF (0.3 ºC) to 1 ºF (0.6 ºC) lower than oral temperature. Readings over 99 ºF (37.2 ºC) may indicate a fever.

How to Measure Tympanic (Ear) Temperature?

Tympanic thermometers are best used in babies over 6 months of age. Babies younger than six months have a narrow ear canal to insert the probe hence it is best to avoid using these thermometers in them. The device needs to be placed correctly in the ear for an accurate reading. If the baby has a lot of earwax, then the reading may be incorrect.

Here’s how to take the ear temperature of a baby:

  1. Position the tip of the thermometer in the ear canal. Ensure to insert the tip only till the mark.
  2. Based on the thermometer the reading time may vary. Read the instructions on the manual to know how long to keep the thermometer.
  3. As these thermometers are sensitive to placement, you may need to take a few readings to get the accurate temperature.

The ear temperature of a baby is 0.5 ºF (0.3 ºC) to 1 ºF (0.6 ºC) higher than oral temperature. If you baby has a temperature of over 100.4 ºF or 38 ºC then he may have a fever.

Taking Armpit Temperature of Baby?

Axillary Thermometer

Axillary thermometers are known to be less reliable compared to the others. Although it can be used at any age, it is recommended that you do not use these in babies younger than 3 months as the reading may not be precise.

To measure the armpit temperature of your baby:

  1. Undress your baby over the waist and hold him in a sitting position.
  2. Ensure that the underarm of the baby is dry. Rub cotton dipped in alcohol to clean the tip of the thermometer.
  3. Place the tip in the baby’s armpit and gently hold the elbow close to the baby’s body.
  4. Hold the thermometer in position until it shows a reading or beeps.
  5. Remove the thermometer and clean the tip with alcohol before storing it.

The normal body temperature for infants under the arm is 0.5 ºF (0.3 ºC) to 1 ºF (0.6 ºC) lower than the oral temperature. A temperature reading higher than 99 ºF (37.2 ºC) under the arm usually indicates a fever.

How to Take Oral Temperature of a Baby?

Oral Thermometer

An oral thermometer is recommended for children over the age of four as the child is old enough to hold the thermometer in place himself. If you are using a standard digital thermometer, then you should use different devices for rectal and oral temperature to avoid any infection. Keep in mind that the child should not have consumed anything hot or cold at least 30 minutes prior to measuring the oral temperature.

Here are a few steps you can consider while measuring your baby’s oral temperature:

  1. Clean the thermometer with alcohol and place it between the tongue and the lower palette in the mouth. The thermometer should be held in place with the tongue and the lips and not with the teeth.
  2. Although the child is old enough to hold it in place, do not leave him unattended with it.
  3. Keep it in position for about three minutes and note the temperature.
  4. After use, wipe it with alcohol and store it safely.

How to Ensure The Accuracy of the Reading?

Following the step by step instructions on the manual can help get an accurate reading. You can also keep in mind the following aspects to get an accurate reading:

  • Allow at least 15 minutes after your baby has had a bath before you measure his temperature, as bathing increases body temperature.
  • Do not take the temperature at least for 30 minutes after your child has eaten anything hot or cold.
  • If the baby is wrapped tightly or your child is wearing too many clothes, allow them time to cool off before taking the temperature.

Things to Remember

Keep in mind the following things before and after using a digital thermometer on your baby.

  • Keep separate thermometers for oral and rectal temperature measurement.
  • Follow the instructions on the manual to get accurate results.
  • Keep the thermometer out of the reach of children to prevent possible choking hazards.
  • Clean the thermometer thoroughly with alcohol before and after use to prevent bacteria and infections.


It is essential that you measure the accurate temperature of your child to determine whether he has fever and a digital thermometer gets you the best results. The right procedures can help you record the temperature of your baby and take further steps accordingly.

Also Read: Fever In Babies