Use a digital thermometer to check your child’s temperature.
Don’t use a mercury thermometer. There are different kinds and uses of digital
thermometers. They include:
Rectal. For children younger than 3 years, a rectal temperature is the
Forehead (temporal). This works for children age 3 months and older. If a
child under 3 months old has signs of illness, this can be used for a first pass.
The provider may want to confirm with a rectal temperature.
Ear (tympanic). Ear temperatures are accurate after 6 months of age, but
Armpit (axillary). This is the least reliable but may be used for a first
pass to check a child of any age with signs of illness. The provider may want to
confirm with a rectal temperature.
Mouth (oral). Don’t use a thermometer in your child’s mouth until they are
at least 4 years old.
Use the rectal thermometer with care. Follow the product maker’s directions for
correct use. Insert it gently. Label it and make sure it’s not used in the mouth.
may pass on germs from the stool. If you don’t feel OK using a rectal thermometer,
ask the healthcare provider what type to use instead. When you talk with any
healthcare provider about your child’s fever, tell them which type you used.
Below are guidelines to know if your young child has a fever. Your child’s healthcare
provider may give you different numbers for your child. Follow your provider’s
Fever readings for a baby under 3 months old:
- First, ask your child’s healthcare provider how you should take the
- Rectal or forehead: 100.4°F (38°C) or higher
- Armpit: 99°F (37.2°C) or higher
Fever readings for a child age 3 months to 36 months (3 years):
- Rectal, forehead, or ear: 102°F (38.9°C) or higher
- Armpit: 101°F (38.3°C) or higher
Call the healthcare provider in these cases:
- Repeated temperature of 104°F (40°C) or higher in a child of any age
- Fever of 100.4° F (38° C) or higher in baby younger than 3 months
- Fever that lasts more than 24 hours in a child under age 2
- Fever that lasts for 3 days in a child age 2 or older