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How to use the Fahrenheit to Celsius
- 1Type the value you want to convert.
- 2The result updates instantly as you type.
- 3Use the swap button to convert in the other direction, or check the chart below.
How to convert 104 °F to Celsius
Subtract 32, then multiply by 5/9: (104 − 32) × 5/9 = 40 °C. Quick estimate: subtract 30 and halve it, which gives 37 °C (close for everyday temperatures).
Is 104 °F a fever?
Yes. 104 °F (40 °C) is a fever: most doctors define fever as 100.4 °F (38 °C) or higher. At 103 °F (39.4 °C) and above, adults should contact a doctor, and babies or anyone who seems very unwell should get urgent care.
Temperatures measured in the mouth, ear, armpit and forehead differ slightly; armpit readings are usually the lowest.
Nearby values
| Fahrenheit | Celsius |
|---|---|
| 100 °F | 37.8 °C |
| 100.4 °F | 38 °C |
| 101 °F | 38.3 °C |
| 102 °F | 38.9 °C |
| 103 °F | 39.4 °C |
| 104 °F | 40 °C |
| 105 °F | 40.6 °C |
| 110 °F | 43.3 °C |
| 120 °F | 48.9 °C |
| 150 °F | 65.6 °C |
| 180 °F | 82.2 °C |
Popular conversions
Frequently asked questions
What is 104 °F in Celsius?
104 °F is 40 °C: (104 − 32) × 5/9.
What is 104 °F in Kelvin?
104 °F is 313.15 K (add 273.15 to the Celsius value).