Body temperatures vary slightly from person to person and at different times of day. The average temperature has traditionally been defined as 98.6 F (37 C). A temperature taken using a …

Oct 14, 2025 · Temperatures between 99.5°F and 100.3°F are sometimes called low-grade fevers, while readings above 105°F (40.6°C) are far more dangerous and require immediate …

May 31, 2023 · There are no strict guidelines for what temperature is a fever, because body temperature varies by person, time of day and method of measurement. But healthcare …

Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with body temperature exceeding the normal range caused by an increase in the body's …

Fever means a body temperature of 100.4° F (38°C) or higher. While any temperature above your normal temperature range is considered a fever, there are different levels of fever severity: …

Jul 27, 2025 · Learn what can cause a fever and how to know when a fever can be dangerous.

Jun 20, 2024 · Doctors generally consider a fever to be an oral temperature of 100 F (37.8 C) or higher. When you have an infection or illness, your body releases substances that tell its …

Jan 20, 2025 · A fever is defined as a body temperature of 38°C (100.4°F) or higher. Normal body temperature is usually 37°C (98.6°F), although it can be about a half degree Celsius higher or …

Dec 11, 2025 · 99 degrees isn’t usually considered a fever. But if you have other symptoms like cough, congestion or a runny nose, you may be sick. The medical community generally …

Sep 3, 2025 · In adults, the average body temperature measured orally (by mouth) is 98.0 F (36.7 C), with an approximate range between 95.5 F and 99.9 F. 2.