Temperature Converter (°C, °F, K, °R, °Ré

Thermodynamic Temperature Scales & Physical Benchmarks

Temperature measures the average microscopic kinetic energy of atoms and molecules in a substance.

The Major Temperature Scales

• Celsius (°C): Standard international metric scale based on the freezing (0°C) and boiling (100°C) points of water at 1 atm.

• Fahrenheit (°F): Customary US scale defined with water freezing at 32°F and boiling at 212°F (an exact 180° interval).

• Kelvin (K): Absolute SI thermodynamic scale starting at Absolute Zero, where all classical thermal motion ceases.

• Rankine (°R): Absolute thermodynamic scale using Fahrenheit-sized degree intervals.

Crucial Benchmark Temperatures

• Absolute Zero: -273.15°C

• Water Freezes: 0.00°C

• Normal Human Body: 37.00°C

• Water Boils (1 atm): 100.00°C

• Surface of the Sun: ~5,500°C

How to Use This Calculator

Enter your Temperature Value (e.g. 100) and Input Temperature Scale — choose from Celsius (°C), Fahrenheit (°F), Kelvin (K, Absolute SI Scale). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Exact thermodynamic temperature conversion formulas:: ^ = (^ × (9) / (5)) + 32 = (^ × 1.8) + 32: ^ = (^ - 32) × (5) / (9) = ^ - 321.8: K = ^ + 273.15 = ^ + 459.671.8: ^ = ^ + 459.67 = K × 1.8: ^ = ^ × 0.8

Worked Example

For example, converting the boiling point of pure water at sea level (100°C): . In absolute thermodynamic temperature, this equals 373.15 K and 671.67^.

Understanding Your Result

Key temperature reference points: Absolute zero 0 K / −273.15°C / −459.67°F. Water freezes at 0°C / 32°F / 273.15 K. Water boils at 100°C / 212°F / 373.15 K at 1 atm (sea level). Human body temperature 37°C / 98.6°F. Oven baking range: 150–230°C / 300–450°F. Kelvin is always used in thermodynamic equations — never negative. Temperature differences in Celsius and Kelvin are equal: a 10°C rise = a 10 K rise.