Taking Your Child's Temperature
A complete guide to temperature-taking methods for children of all ages
When Your Child Feels Warm
When your child feels warm or seems out of sorts, knowing if a fever might be the cause can be helpful.
Here's how to take your child's temperature, safely and accurately.
What Type of Thermometer Should I Use?
Digital thermometers give the quickest, most accurate readings, and are the only kind that doctors currently recommend.
Three Types Are Available:
Regular Digital Thermometers
These are straight with a temperature sensor at the tip and an easy-to-read digital display.
Can be used to measure: Rectal, oral, or axillary (armpit) temperatures
Ear Digital Thermometers
Measure the heat waves from the eardrum through a plastic probe put inside the ear.
⚠️ Age Requirement: For use only with kids 6 months of age and older
Temporal Artery Digital Thermometers
Measure heat waves from the temporal artery, a blood vessel that passes just below the skin across the forehead.
Can be used for: Kids of all ages and adults
Note: Temporal artery thermometers made by different manufacturers have slightly different instructions for use, so read the package insert if you use one.
Tip: Check the manufacturer's instructions to see what the thermometer is designed for and how it signals that the reading is complete.
⛔ Thermometers NOT Recommended
Some types of thermometers aren't recommended because they're less accurate. These include:
❌ Plastic Strip Thermometers
Not accurate enough for medical use
❌ Pacifier Thermometers
Unreliable readings
❌ Smartphone Temperature Apps
Not medically accurate
❌ Glass Thermometers
Not safe - never use these!
Important Safety Warning
Don't use a glass thermometer, as these aren't safe. Old mercury thermometers can break and pose serious health risks.
Tips for Taking Temperatures by Age
As any parent knows, taking a squirming child's temperature can be a challenge.
The best method will depend on a child's age and how well they can cooperate.
Taking Temperature by Age:
👶 Babies Younger Than 3 Months Old
Best method: A rectal temperature is best.
🍼 Babies 3 to 6 Months Old
Best method: A rectal temperature is best
Also acceptable: You can use a temporal artery or axillary method
🧸 Kids 6 Months to 3 Years Old
Best method: A rectal temperature is best
Also acceptable: You can use a temporal artery, ear, or axillary method
🧒 Kids 4 Years or Older
Best method: An oral temperature is best if child can properly hold the thermometer under the tongue
If not: You can use a rectal, temporal, ear, or axillary method
Important Tips for Accurate Readings
Whatever method you choose, keep these tips in mind:
Avoid Taking Temperature After:
- •A bath
- •If they were under blankets or in multiple layers
- •If swaddled (for infants)
This can affect the temperature reading and give falsely high results.
Always Supervise
Stay with your child while you take their temperature. Never leave them unattended with a thermometer.
🎯Quick Reference: Choosing the Right Method by Age
👶Birth to 3 Months
Best Method: Rectal
This is the most accurate method for young infants. Any fever in a baby under 3 months is serious and needs immediate medical attention.
Learn Rectal Method →🧒3 Months to 4 Years
Options: Rectal (most accurate), Armpit, or Ear
Rectal is still most accurate, but armpit is easier and works well for routine checks.
Understanding Normal Body Temperature
Normal body temperature isn't just one number—it varies throughout the day and can be different depending on where you measure it. Understanding what's normal helps you recognize when your child might have a fever.
The "normal" temperature of 98.6°F (37°C) is actually just an average. A child's normal temperature can range from about 97°F (36.1°C) in the morning to 100°F (37.8°C) in the late afternoon or after physical activity. Body temperature also rises slightly after eating or when a child is bundled up.
Normal Temperature Ranges
Rectal:
97.9°F to 100.4°F (36.6°C to 38°C)
Oral:
95.9°F to 99.5°F (35.5°C to 37.5°C)
Armpit:
94.5°F to 99.1°F (34.7°C to 37.3°C)
Ear:
96.4°F to 100.4°F (35.8°C to 38°C)
Remember: Every child is unique. It's helpful to know your child's normal temperature range when they're healthy, so you can better recognize when they have a fever.
When to Call the Doctor About a Fever
While fever itself isn't usually dangerous, it can be a sign of illness that needs medical attention. The age of your child and other symptoms matter more than the exact temperature number.
🚨 Call Immediately If:
- •Your baby is younger than 3 months and has a rectal temperature of 100.4°F (38°C) or higher
- •Your child has a seizure
- •Your child appears very ill, is unusually drowsy, or very fussy
- •Your child has been in a very hot place, such as an overheated car
📞 Call Your Doctor If:
- •Your child is 3-6 months old with a temperature of 101°F (38.3°C) or higher
- •Your child is older than 6 months with a temperature of 103°F (39.4°C) or higher
- •Fever lasts more than 24 hours in a child younger than 2 years
- •Fever lasts more than 3 days in a child 2 years or older
- •Your child has other symptoms like rash, sore throat, earache, vomiting, or diarrhea
- •Fever goes away for more than 24 hours and then comes back
Trust your instincts. If your child seems very sick or you're worried, don't hesitate to call your doctor. It's always better to be safe and get professional medical advice when you're concerned about your child's health.
Keeping Track of Your Child's Temperature
When your child is sick, it's helpful to keep a record of their temperature readings. This information can be valuable when you talk to your doctor and helps you see patterns in your child's illness.
Each time you take your child's temperature, write down the date, time, temperature reading, and which method you used (rectal, oral, armpit, or ear). Also note any medications you gave and when, along with other symptoms your child is experiencing.
For example: "January 15, 3:00 PM - 101.5°F (oral) - gave ibuprofen - child has runny nose and cough." This detailed record helps your healthcare provider make better decisions about your child's care.
📝 What to Record:
- • Date and time of reading
- • Temperature number
- • Method used (oral, rectal, etc.)
- • Medications given and when
- • Other symptoms present
- • Child's behavior and activity level
📱 Tracking Options:
- • Paper notebook or journal
- • Notes app on your phone
- • Health tracking app
- • Calendar with notes
- • Whatever works best for you!
Why Accurate Temperature Readings Matter
Getting an accurate temperature reading is more important than you might think. It's not just about knowing if your child has a fever—it's about having reliable information to guide medical decisions.
For infants under 3 months, even a slight fever can indicate a serious infection that needs immediate medical attention. An inaccurate reading could delay important treatment or cause unnecessary worry and emergency room visits.
That's why doctors recommend digital thermometers and specific methods for different ages. These recommendations aren't arbitrary—they're based on research showing which methods give the most reliable results for each age group.
Taking the time to use the right method and technique ensures that:
- ✓You can confidently report accurate information to your doctor
- ✓You make informed decisions about when to seek medical care
- ✓You can track whether fever is improving or getting worse
- ✓You avoid unnecessary worry from inaccurate readings
⚖️Comparison of Temperature Methods
| Method | Accuracy | Best Age | Fever Threshold |
|---|---|---|---|
| Rectal | Most Accurate | 0-3 years | 100.4°F (38°C) |
| Oral | Accurate | 4+ years | 100°F (37.8°C) |
| Ear | Accurate | 6+ months | 100.4°F (38°C) |
| Armpit | Less Accurate | All ages | 99°F (37.2°C) |
| Forehead | Varies | All ages | 100.4°F (38°C) |
💡General Tips for All Methods
✓ Always:
- • Use digital thermometers only
- • Clean before and after each use
- • Wait if child just bathed/exercised
- • Record the reading and time
- • Note which method you used
- • Keep child calm and still
✗ Never:
- • Use glass mercury thermometers
- • Leave child unattended with thermometer
- • Force a method if child very resistant
- • Mix up oral and rectal thermometers
- • Take reading right after eating/drinking
- • Rely on touch alone to assess fever