104°F to °C — What is 104 Fahrenheit in Celsius?
104°F = 40°C. Use the exact formula (°F − 32) × 5/9 to convert any Fahrenheit temperature to Celsius — algebraically exact with zero rounding, as defined by the NIST.
Answer
104 °F = 40 °C
Exact: 40.000000 °C · uses the BIPM-defined constant
How it's calculated
(°F − 32) × 5/9 = °C
Step 1: Apply the formula to the input value.
Step 2: (104 − 32) × 5/9 = 72 × 5/9 = 40
What does 104°F feel like?
104°F is hot. Water boils at 212°F at sea level. This range is common for cooking methods: simmering (180–200°F), pasteurisation (161°F), and hot beverages (150–175°F).
Common temperature references
Key temperatures from science, cooking, and medicine
| °C | °F | Reference |
|---|---|---|
| -40°C | -40°F | °C and °F are equal |
| -18°C | 0°F | Zero Fahrenheit |
| 0°C | 32°F | Water freezes |
| 10°C | 50°F | Cool day |
| 20°C | 68°F | Room temperature |
| 25°C | 77°F | Warm room |
| 37°C | 98.6°F | Body temperature |
| 38°C | 100.4°F | Fever threshold (WHO) |
| 100°C | 212°F | Water boils (sea level) |
| 160°C | 320°F | Low oven |
| 180°C | 356°F | Moderate oven (Gas Mark 4) |
| 200°C | 392°F | Hot oven (Gas Mark 6) |
| 220°C | 428°F | Very hot oven (Gas Mark 7) |
| 250°C | 482°F | Max home oven |
Fahrenheit to Celsius — Nearby Values
Click any row to open its full conversion page
| Fahrenheit (°F) | Celsius (°C) |
|---|---|
| 104 °Fthis page | 40 °C |
Common questions about 104 °F to °C
What is 104°F in Celsius?
104 degrees Fahrenheit equals exactly 40 degrees Celsius. The formula is (104 − 32) × 5/9 = 40°C. In Kelvin, this is 313.15 K.
How do you convert 104°F to °C step by step?
Step 1: Subtract 32 from 104 to get 72. Step 2: Multiply by 5/9 (or 0.5556). Result: 72 × 5/9 = 40°C. This formula is algebraically exact.
Is 104°F hot or cold?
104°F is very hot. Extreme heat conditions — limit outdoor activity.
What is 40°C back in Fahrenheit?
40°C converts back to exactly 104°F — which is 104°F. The conversion is perfectly reversible using the inverse formula: (°C × 9/5) + 32.
Is 104°F a fever?
The WHO defines fever as body temperature above 100.4°F (38°C). 104°F is a high fever — seek immediate medical attention.
What should I wear at 104°F?
At 104°F, extreme heat clothing: lightest possible fabrics, wide-brim hat, frequent water breaks. Avoid outdoor exertion during midday. Seek air-conditioned spaces.
Related Fahrenheit to Celsius Conversions
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Celsius
104 °F=40 °C
Formula used
(°F − 32) × 5/9 = °C
Algebraically exact — zero rounding in the formula