What Is 38°C in Fahrenheit?
38 degrees Celsius is exactly 100.4 degrees Fahrenheit.
How to Convert Celsius to Fahrenheit
To convert degrees Celsius to degrees Fahrenheit, multiply by 9/5, then add 32.
For example: 25 °C × 9/5 = 45, and 45 + 32 = 77 °F.
Where You Meet This Number
Thirty-eight degrees is the threshold most health services use to define a fever, which makes it the reading people look up most often after taking a temperature. Its American equivalent, 100.4 °F, is the figure US guidance uses for the same line.
A thermometer showing 38.0 °C is 100.4 °F — the point at which most guidance starts calling it a fever.
What People Get Wrong
Where you measure changes the number. An ear or forehead reading can differ from an oral one by several tenths, and an armpit reading typically runs about 0.5 °C lower. Compare like with like before concluding anything.
Body Temperatures in Celsius and Fahrenheit
| Degrees Celsius (°C) | Degrees Fahrenheit (°F) |
|---|---|
| 36 | 96.8 |
| 36.5 | 97.7 |
| 37 | 98.6 |
| 37.5 | 99.5 |
| 38 | 100.4 |
| 38.5 | 101.3 |
| 39 | 102.2 |
| 39.5 | 103.1 |
| 40 | 104 |
| 40.5 | 104.9 |
| 41 | 105.8 |
| 42 | 107.6 |
About These Scales
Degree Celsius
The Celsius scale puts the freezing point of water at 0 degrees and its boiling point at 100 degrees at sea level. It is the everyday temperature scale in nearly every country except the United States.
Degree Fahrenheit
On the Fahrenheit scale water freezes at 32 degrees and boils at 212 degrees, so one Fahrenheit degree is 5/9 the size of a Celsius degree. It remains the standard scale for weather, ovens and body temperature in the United States.
Definitions follow The SI Brochure, BIPM. See how we calculate for the exact values and rounding rules.
Frequently Asked Questions
Is 38 °C a fever?
Yes, by the usual definition. 38 °C, or 100.4 °F, is the threshold both UK and US health services use.
When should a fever be seen by a doctor?
Guidance varies by age and circumstance, and a number alone does not decide it. Contact a doctor if a fever is very high, persists, or comes with symptoms that worry you — and immediately for an infant under three months with any fever.
What is 39 °C in Fahrenheit?
39 °C is exactly 102.2 °F, which counts as a high fever.
What is 38.5 °C in Fahrenheit?
38.5 °C is exactly 101.3 °F, comfortably above the fever threshold.