Temperature Converter — Understanding Temperature Scales
Temperature is measured on several different scales. While most of the world uses Celsius, the United States primarily uses Fahrenheit, and science uses Kelvin. Knowing how to convert between them is an essential skill for cooking, science, weather understanding, and international communication.
The Four Temperature Scales
- Celsius (°C): The international standard. Water freezes at 0°C and boils at 100°C at standard pressure. Used in most countries for weather, cooking, and medicine.
- Fahrenheit (°F): Used primarily in the United States. Water freezes at 32°F and boils at 212°F. Human body temperature is 98.6°F.
- Kelvin (K): The SI unit for temperature. Starts at absolute zero (−273.15°C), the coldest possible temperature. Used in physics, chemistry, and astronomy. There are no negative Kelvin values.
- Rankine (°R): Like Kelvin but based on Fahrenheit degrees. Absolute zero is 0°R. Used in some US engineering applications.
Conversion Formulas
- °F to °C: (°F − 32) × 5/9
- °C to °F: (°C × 9/5) + 32
- °C to K: °C + 273.15
- K to °C: K − 273.15
Important Temperature Reference Points
- Absolute Zero: −273.15°C / −459.67°F / 0 K
- Water Freezing: 0°C / 32°F / 273.15 K
- Room Temperature: ~22°C / 72°F / 295 K
- Human Body: 37°C / 98.6°F / 310.15 K
- Water Boiling: 100°C / 212°F / 373.15 K
- Sun Surface: ~5,500°C / ~9,932°F / ~5,773 K
Practical Uses
- Cooking: Oven temperatures in US recipes are in °F; European recipes use °C.
- Weather: Understanding temperature forecasts when traveling internationally.
- Science: Chemical reactions, gas laws, and thermodynamics all use Kelvin.
- HVAC & Engineering: Heating and cooling systems in the US use °F and Rankine.