Body temperature norms: MedlinePlus Medical Encyclopedia

Normal body temperature varies by person, age, activity, and time of day. The average normal body temperature is generally accepted as 98.6°F (37°C). Some studies have shown that the "normal" body temperature can have a wide range, from 97°F (36.1°C) to 99°F (37.2°C).

A temperature over 100.4°F (38°C) most often means you have a fever caused by an infection or illness.

Body temperature normally changes throughout the day and in adults, it is lowest in the early morning.

Normal body temperature; Temperature - normal

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Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.