Convert Fahrenheit (°F) & Celsius (°C)

Convert to Fahrenheit

T × 9 5 + 32
  • T = Celsius

Convert to Celsius (centigrade)

( T 32 ) × 5 9
  • T = Fahrenheit


1. Convert 37°C to Fahrenheit.

37 × 9 5 + 32

The answer is 98.6°F.

2. Convert 98.6°F to Celsius.

( 98.6 32 ) × 5 9

The answer is 37°C

Medical Relevance

Core temperature
The temperature of the deep tissues of the body—the “core” of the body—remains almost exactly constant, within ±1°F (±0.6°C), day in and day out except when a person febrile illness.
Normal core temperature
The average normal core temperature is generally considered to be between 98.0° and 98.6°F when measured orally and about 1°F higher when measured rectally.
Occurs between 105—108°F. Circulatory shock, cell destruction and organ failure are followed by death.
Occurs between 94—77°F. Once the core temperature falls below 85°F temperature regulation is lost. Death by cardiac arrest or ventricular fibrillation occurs once body temperature falls to 77°F.

Temperature Assessment Sites

  • Pulmonary artery (most accurate)
  • Esophageal
  • Bladder
  • Rectal
  • Tympanic
  • Oral
  • Axillary
  • Forehead (least accurate)
Reference temperatures
Rectal Oral Tympanic Axillary
37.5 37 36.8 36.4
99.5 98.6 98.2 97.6
Actual average temperatures collected in three clinical studies. Population sizes 7,636, 1,000 and 433.
Rectal Tympanic Oral Axillary Forehead
37.04 36.64 36.57 35.97 35.09
98.67 97.95 97.82 96.74 95.16


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