°C to °F Converter
Convert °C to °F: °F = °C × 9/5 + 32. Formula, worked example, table of common values and scale definitions.
Result104 °F
0 °C = 32 °F (scales with different zero points need a formula, not one factor)
40 °C =
104 °F
Formula
°F = °C × 9/5 + 32 °C = (°F − 32) × 5/9
Worked example
- °F = °C × 9/5 + 32 with 40 °C gives 104 °F
Common values
| °C | °F |
|---|---|
| -40 | -40 |
| 0 | 32 |
| 20 | 68 |
| 30 | 86 |
| 40 | 104 |
| 70 | 158 |
| 90 | 194 |
| 100 | 212 |
Unit definitions
| Unit | Reference point | What it is |
|---|---|---|
| °C | 0 °C = 273.15 K | Degree Celsius. 0 °C is the freezing point of water at standard pressure; the size of a degree equals one kelvin. |
| °F | 32 °F = 273.15 K | Degree Fahrenheit. A Fahrenheit degree is 5/9 of a kelvin. |
Frequently asked questions
What is the formula to convert °C to °F?
°F = °C × 9/5 + 32. To go back, °C = (°F − 32) × 5/9.
At what temperature are Celsius and Fahrenheit equal?
At −40 °C, which is also −40 °F.
How do I convert a temperature difference?
Multiply the difference by 9/5 and do not add 32. A rise of 10 °C is a rise of 18 °F.
Related
Opposite direction: °F to °C
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