Temperature
°C, °F, Kelvin
About This Calculator
Temperature can be expressed in Celsius (metric), Fahrenheit (imperial), or Kelvin (absolute scientific scale). Each scale has different zero points and step sizes, requiring formulas rather than simple multiplication to convert between them.
Formula
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
K = °C + 273.15
Example Calculation
Convert body temperature 37°C to Fahrenheit and Kelvin.
- °F = (37 × 9/5) + 32 = 66.6 + 32 = 98.6°F
- K = 37 + 273.15 = 310.15 K
37°C = 98.6°F = 310.15 K
Key Reference Temperatures
| Reference Point | °C | °F | K |
|---|---|---|---|
| Absolute zero | -273.15 | -459.67 | 0 |
| Water freezes | 0 | 32 | 273.15 |
| Room temperature | 20 | 68 | 293.15 |
| Body temperature | 37 | 98.6 | 310.15 |
| Water boils | 100 | 212 | 373.15 |
Frequently Asked Questions
Why does Fahrenheit exist if Celsius is simpler?
Fahrenheit was established before Celsius and remains the official temperature scale in the United States. Celsius is used in most other countries and in all scientific contexts.
What is absolute zero?
Absolute zero (0 K = -273.15°C = -459.67°F) is the lowest possible temperature, where all molecular motion theoretically stops. It has never been fully achieved in practice.
Is a degree Celsius the same size as a Kelvin?
Yes. A change of 1°C is exactly equal to a change of 1 K. The two scales differ only by their zero point: 0°C = 273.15 K.
What temperature is the same in Celsius and Fahrenheit?
-40 degrees is the point where Celsius and Fahrenheit are equal: -40°C = -40°F. You can verify this with the conversion formula.