What Is the Normal Body Temperature for Adults?

Under normal circumstances, body temperature in adults is most commonly measured in the axilla (armpit), and mercury-in-glass thermometers are still widely used for this purpose. So, what is considered a normal body temperature for adults?

Normal Adult Body Temperature

There are several methods for measuring body temperature, and the recorded values may vary slightly depending on the measurement site. For instance, mercury or digital thermometers can be used to measure temperature in the axilla, orally (under the tongue), or rectally. Normal axillary temperature in adults ranges from approximately 36.0°C to 37.0°C; normal oral temperature ranges from 36.3°C to 37.2°C; and normal rectal temperature ranges from 36.5°C to 37.7°C. Infrared thermometers—such as forehead (temporal) and tympanic (ear) thermometers—may also be used. Normal forehead temperature ranges from 35.0°C to 37.0°C, while normal tympanic temperature ranges from 35.7°C to 37.7°C.

In healthy individuals, baseline body temperature varies slightly among individuals and may fluctuate slightly due to internal and external factors. Within a 24-hour period, body temperature tends to be slightly higher in the afternoon than in the morning. It may also rise modestly following vigorous exercise, heavy physical labor, or eating—but such fluctuations generally remain within a 1°C range. Prolonged exposure to high ambient temperatures can likewise cause a slight increase in body temperature. Additionally, women often experience a mild elevation in body temperature just before menstruation and during pregnancy.

Elderly individuals typically have lower basal metabolic rates, resulting in relatively lower average body temperatures compared with younger and middle-aged adults. Wishing you good health and happiness!