The normal body temperature varies depending on a variety of factors, including a person’s age, gender, and degree of activity.
The usual body temperature for an adult is approximately 98.6°F (37°C), however every person’s baseline body temperature is somewhat different, and may be regularly a little higher or lower than the normal temperature.
In this post, we’ll go through the normal temperature ranges for adults, children, and babies, among other things. We also explore elements that alter body temperature, as well as when it is appropriate to seek medical attention.
Chart of normal body temperature
The temperature of a person’s body varies based on where the measurements are taken on his or her person. Rectal readings are often higher than mouth readings, whereas armpit readings are generally lower than rectal readings.
This table lists the typical body temperature ranges for adults and children, according to, the manufacturer of the thermometer used in this study:
| Type of reading | 0–2 years | 3–10 years | 11–65 years | Over 65 years |
| Oral | 95.9–99.5°F (35.5–37.5°C) | 95.9–99.5°F (35.5–37.5°C) | 97.6–99.6°F (36.4–37.6°C) | 96.4–98.5°F (35.8–36.9°C) |
| Rectal | 97.9–100.4°F (36.6–38°C) | 97.9–100.4°F (36.6–38°C) | 98.6–100.6°F (37.0–38.1°C) | 97.1–99.2°F (36.2–37.3°C) |
| Armpit | 94.5–99.1°F (34.7–37.3°C) | 96.6–98.0°F (35.9–36.7°C) | 95.3–98.4°F (35.2–36.9°C) | 96.0–97.4°F (35.6–36.3°C) |
| Ear | 97.5–100.4°F (36.4–38°C) | 97.0–100.0°F (36.1–37.8°C) | 96.6–99.7°F (35.9–37.6°C) | 96.4–99.5°F (35.8–37.5°C) |
It is normal for body temperature readings to fluctuate within these ranges depending on the following variables:
- a person’s age and sex
- the time of day, typically being lowest in the early morning and highest in the late afternoon
- high or low activity levels
- food and fluid intake
- for females, the stage in their monthly menstrual cycle
- the method of measurement, such as oral (mouth), rectal (bottom), or armpit readings
Adult temperature
When taken orally, a typical adult body temperature can range between 97.6 and 99.6 degrees Fahrenheit, while different sources may provide slightly different figures.
The following temperatures in adults indicate that someone is suffering from a fever:
- at least 100.4°F (38°C) is a fever
- above 103.1°F (39.5°C) is a high fever
- above 105.8°F (41°C) is a very high fever
Researchers have looked examined the variances in typical body temperatures across persons who live in different places. Among nearly 35,000 participants in a study, researchers discovered that older folks had the lowest temperatures and that African-American women had higher temperatures than white men.
Researchers discovered that some medical disorders can have an impact on a person’s body temperature. People with an underactive thyroid (hypothyroidism), for example, tended to have lower temperatures, but people with cancer tended to have higher temperatures.
Children temperature
An oral temperature measurement of 95.9°F–99.5°F indicates a normal body temperature for children aged 3–10 years.
Children and adults tend to have body temperatures that are similar.
Infants temperature
When it comes to armpit and ear temperature measures, newborns and young children might sometimes have larger body temperature ranges than adults.
Infants aged 0–2 years have a normal body temperature that ranges between 97.9 and 100.4 degrees Fahrenheit when measured rectally. When a baby is teething, his or her body temperature may rise a little.
The average body temperature of a newborn is 99.5°F.
When compared to their body weight, a baby has a bigger surface area on which to radiate heat, which raises their temperature. Their bodies are also more metabolically active, which results in an increase in heat production.
The bodies of babies do not regulate their temperature as well as the bodies of adults. When it is warm, they sweat less, which means that their bodies retain more heat. A fever might also make cooling down more difficult for those who are suffering from it.
When to visit your doctor
A person’s risk of developing a hazardous body temperature is dependent on their age:
Adults
In otherwise healthy persons, a temperature of 100.4–104°F produced by a short-term sickness should not create any serious health consequences. A mild temperature, on the other hand, can be extremely concerning for someone who already has heart or lung problems.
Call a doctor if your temperature is higher than 104°F or lower than 95° F, especially if you are experiencing other symptoms such as confusion, headaches, or shortness of breath. Temperatures greater than 105.8°F have been shown to cause organ failure.
Hypothermia is defined by doctors as a body temperature that falls below 95°F. If hypothermia is not treated promptly, it can be life-threatening.
Children
Children between the ages of three months and three years who have a fever but whose temperature is less than 102°F do not usually require medical treatment. If your kid has a temperature greater than 102.2°F, or if he or she has a lower temperature but is experiencing dehydration, vomiting, or diarrhoea, call your doctor.
Babies
If a child under the age of three months has a rectal temperature of 100.4°F or above, seek emergency medical assistance immediately. A small temperature in a very young baby can indicate the presence of a dangerous infection.
How to check your body temperature
There are many different types of thermometers available, and the most appropriate approach depends on the age of the individual being measured:
| Age | Best method |
| 0 to 3 months | Rectal |
| 3 months to 3 years | Rectal, ear, or armpit |
| 4 to 5 years | Oral, rectal, ear, or armpit |
| 5 years to adult | Oral, ear, or armpit |
To use the thermometer, follow the directions on the packaging.
If a temperature measurement is abnormally high or low, take another reading after 5 to 10 minutes to confirm the reading. In the event that a person is doubtful whether or not the reading is correct, they can take another reading with another thermometer.
What factors influence the body’s temperature?
The hypothalamus is a part of the brain that is responsible for controlling body temperature. When the body temperature climbs over or falls below the 98.6°F (37°C) level, the hypothalamus is activated, allowing the temperature to be regulated.
When the body becomes too cold, the hypothalamus sends signals to the body, causing it to shiver, which helps to warm the body. When the body becomes overheated, it sends signals to the brain to begin sweating, which allows heat to escape the body.
The majority of fevers are caused by infections. An illness causes a fever, which is the body’s natural way of responding to and battling the infection.
The signs and symptoms of a fever
A fever is defined as a body temperature that reaches or surpasses 100.4°F according to medical professionals. Other signs and symptoms include:
- appetite loss
- chills
- a headache
- irritability
- muscle aches
- shivering
- sweating
- weakness
Conclusion
The optimal body temperature for humans is approximately 98.6°F, but this fluctuates depending on factors such as age, gender, physical activity, and overall health. The temperature of the body fluctuates throughout the day. A fever is defined as a temperature greater than 100.4°F.
Even though babies’ body temperatures may be greater than those of adults, even a minor fever in babies can indicate a serious infection.
Body temperatures measured from various body parts provide a range of temperatures that doctors regard to be normal. Generally, rectal readings are greater than oral readings, while armpit readings are lower than mouth readings.
In the event that a person has an unusually high or low temperature, he or she should seek medical treatment promptly.
Sources
- https://kidshealth.org/en/parents/fever.html
- https://www.welchallyn.com/content/dam/welchallyn/documents/upload-docs/Training-and-Use/Clinical%20In-Service%20Presentations/sure-temp-plus/Normal-Temp-Range-QRC.pdf
- https://www.medicalnewstoday.com/articles/323819
- https://www.bmj.com/content/359/bmj.j5468.full
- https://www.nationwidechildrens.org/family-resources-education/health-wellness-and-safety-resources/helping-hands/temperature-oral-rectal-tympanic-and-axillary-using-digital-thermometers
- https://www.msdmanuals.com/en-gb/home/infections/biology-of-infectious-disease/fever-in-adults
- https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=85&ContentID=P00866
