Taking Your Child's Temperature

It is important to know how to take your child's temperature properly so you can treat his or her illness better. Normal body temperature is 97° to 100° F (36° to 37.8° C) when taken rectally (in the bottom). This can change depending on the time of day, activity level, dress, and the temperature of the surroundings. The axillary (armpit) temperature is about 1° F (0.5° C) lower than oral; the rectal temperature is about 1° F (0.5° C) higher than oral temperature.

Several different types of thermometers are available. Electronic thermometers are very accurate when used properly. Skin strip thermometers are less reliable, so they are not recommended. In a child under 5 years of age, a screening temperature may be taken in the armpit. If the axillary temperature is high, (above 99° F or 37.2° C), you should check it rectally. In children 5 years or older, an oral temperature should be taken.

  • Avoid a glass thermometer unless this is the only thermometer you have.

  • Digital thermometers may be safer and easier to use than glass thermometers.

Use one of the following techniques:

  • Rectal: Lubricate the tip of the thermometer with petroleum jelly. Place the child on his or her stomach and separate the buttocks. Insert the thermometer gently into the anus until the tip is not visible (about ½ to 1 inch or 1 to 2.5 cm). Stop if you feel resistance. Be sure to hold your child while the thermometer is in place. Remove the thermometer:

  • When you hear the signal (digital thermometer).

  • After 3 minutes (glass thermometer).

  • Oral: Place the thermometer under the child's tongue as far back as possible. Have the child hold it in place with the lips or fingers while the mouth is closed.

    Remove the thermometer:

  • When you hear the signal (digital thermometer).

  • After 3 minutes (glass thermometer).

  • Axillary: Place the tip of the thermometer into a dry armpit. Hold the upper arm against the chest before removing and reading the thermometer.

    Remove the thermometer:

  • When you hear the signal (digital thermometer).

  • After 4 to 5 minutes (glass thermometer).