Quick Answer
Celsius and Fahrenheit are two scales for the same quantity. Water freezes at 32 °F (0 °C) and boils at 212 °F (100 °C). The conversion is linear: °F = °C × 9/5 + 32, so a 1 °C step is a 1.8 °F step. 0 °F equals -17.7778 °C.
Key Facts
- 0 °C = 32 °F (water freezing point)
- 100 °C = 212 °F (water boiling point)
- °F = (°C × 9/5) + 32
- °C = (°F − 32) × 5/9
- A 1 °C interval equals a 1.8 °F interval
- US, Liberia, Myanmar use Fahrenheit daily; the rest of the world uses Celsius
Frequently Asked Questions
Which is bigger, a celsiu or a fahrenheit?
Temperature scales measure the same quantity with different zero points and step sizes, so "bigger" does not apply to the unit itself. A 1 °C interval is 1.8 times a 1 °F interval; 0 °C is 32 °F.
How do I convert celsius to fahrenheit?
Use the formula °F = (°C × 9/5) + 32. Example: 25 °C → 25 × 1.8 + 32 = 77 °F. Reverse: °C = (°F − 32) × 5/9.
Why are celsius and fahrenheit different?
They are two different units measuring the same physical quantity. A celsiu is defined as exactly 33.8 °F, and a fahrenheit as exactly -17.2222 °C. Because the units differ in size, the number you write down for the same amount depends on which unit you use - the conversion factor itself is exact, with no rounding.
Is there a quick way to convert without a calculator?
Rough mental math: double the °C value and add 30. Exact: °F = °C × 9/5 + 32.