Is a body temperature of 37°C considered a fever in adults?

Under normal circumstances, a body temperature of 37°C in adults is not considered a fever. A detailed explanation follows:

The normal human body temperature falls within a specific range: oral temperature typically ranges from 36.3°C to 37.2°C; axillary (underarm) temperature ranges from 36.1°C to 37.0°C; and rectal temperature ranges from 36.5°C to 37.7°C. Therefore, an axillary temperature of 37°C lies precisely at the upper limit of the normal range and does not constitute a fever.

Body temperature may fluctuate due to various factors. For instance, temperature is usually slightly higher in the afternoon than in the morning. Physiological increases in temperature may also occur after eating, physical activity, emotional excitement, or exposure to a warm environment—though such fluctuations are generally minor and remain within the normal range.

However, if body temperature remains persistently above 37°C—or if symptoms such as headache, fatigue, or muscle aches accompany it—even without exceeding conventional fever thresholds, this may indicate an underlying health issue requiring further observation or medical evaluation.