All conversions
| Unit | Value | Copy |
|---|---|---|
| Celsius (°C) | — | |
| Fahrenheit (°F) | — | |
| Kelvin (K) | — | |
| Rankine (°R) | — |
Temperature scales have different zero points, so conversion needs an offset as well as a ratio. Enter a value and get every scale at once.
How to use the Temperature Converter
- 1 Type a value in either box — the conversion works in both directions.
- 2 Choose the units to convert temperature from and to, or click any row in the table.
- 3 Use the swap button to reverse the conversion, then copy the result.
Formula
°F = °C × 9/5 + 32 °C = (°F − 32) × 5/9 K = °C + 273.15 °R = K × 9/5
Worked examples
Input: 37 °C
Result: 98.6 °F
310.15 K
Input: 350 °F
Result: 176.67 °C
Reference temperatures
| °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 (sea level) | 100 | 212 | 373.15 |
−40 is the same in both
Celsius and Fahrenheit meet at exactly −40°: −40 °C = −40 °F.
Quick mental conversion
To estimate °F from °C, double it and add 30 (20 °C → ~70 °F). The exact formula is × 1.8 + 32.
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply by 9/5 (1.8) and add 32. For example, 25 °C × 1.8 + 32 = 77 °F.
Can temperature be below 0 K?
No. 0 K (−273.15 °C) is absolute zero, the lowest possible temperature; the converter warns if you go below it.
Why is Kelvin written without a degree sign?
Kelvin is an absolute SI unit, so it is written as K, not °K.
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