38 degrees Celsius = 100.40°F (311.15 K). Use the copy buttons below for any format, or enter a custom value in the converter.
The Celsius scale sets 0°C at the freezing point of water and 100°C at its boiling point. The Fahrenheit scale, used primarily in the United States, sets those same points at 32°F and 212°F. To convert Celsius to Fahrenheit, multiply by 9/5 and add 32: °F = (°C × 9/5) + 32. For 38°C: (38 × 1.8) + 32 = 100.40°F.
38°C
100.40°F
311.15 K
Fahrenheit
100.40°F
Kelvin
311.15 K
Full (°C to °F)
38°C = 100.40°F
Full (°C to K)
38°C = 311.15 K
Low-grade fever
38°C (100.4°F) is the clinical threshold for a fever in adults. At this temperature, the body is mounting an immune response. Rest and hydration are typically recommended.
Enter any Celsius value to convert it live to Fahrenheit and Kelvin.
Here are three everyday situations where knowing that 38°C = 100.40°F makes a practical difference.
If a recipe involves simmering, fermenting, or proofing at 38°C, that's 100.40°F. For example, bread dough proofing at 25–30°C, chocolate tempering at 31–32°C, and sous-vide cooking at 55–65°C all require precise Celsius-to-Fahrenheit conversions when using US kitchen tools.
You're checking the weather for a trip abroad and the forecast shows 38°C. That's 100.40°F. Light, breathable clothing and sun protection are a must. Most weather apps let you switch between °C and °F, but knowing the conversion helps when reading local signage or talking to locals.
In a chemistry or physics class, temperatures are often given in Celsius and need to be converted for US-format worksheets, or converted to Kelvin for thermodynamics problems. 38°C = 100.40°F = 311.15 K. The Kelvin scale is used in the ideal gas law (PV = nRT) and other thermodynamic equations where absolute zero (0 K = −273.15°C) is the reference point.
See how 38°C compares to nearby temperatures in both Celsius and Fahrenheit.
Common questions about 38°C and its Fahrenheit equivalent, answered.