What is the upper limit of normal for body temperature?

The upper limit of normal body temperature is generally considered to be 100.4°F or 38°C. This threshold is significant in clinical settings because it helps to define febrile states, which are often indicative of infection or other medical conditions.

Body temperature can vary based on a variety of factors, including the time of day, the way it is measured (oral, rectal, tympanic, or axillary), and individual characteristics. While a range exists, temperatures above this threshold are categorized as fever, prompting further evaluation and management.

In contrast, the other values provided either fall below this commonly accepted upper limit or do not align with standard clinical definitions of fever, reinforcing the validity of 100.4°F or 38°C as the cut-off point in assessing body temperature in a medical context.