Temperature Converter

Convert temperatures between Celsius, Fahrenheit, Kelvin, and Rankine. Free temperature calculator with conversion formulas and explanations.

Temperature Converter

Understanding Temperature Scales: Theory, Usage, and History

Temperature Scales Explained

Celsius (°C)

Based on water's freezing (0°C) and boiling (100°C) points at standard atmospheric pressure.

Fahrenheit (°F)

Water freezes at 32°F and boils at 212°F. Commonly used in the United States.

Kelvin (K)

Absolute temperature scale starting at absolute zero (-273.15°C). Used in scientific applications.

Rankine (°R)

Absolute scale using Fahrenheit degrees. Primarily used in engineering applications.

Conversion Formulas

Temperature Conversion Formulas:

  • °C to °F: (°C × 9/5) + 32
  • °F to °C: (°F - 32) × 5/9
  • °C to K: °C + 273.15
  • K to °C: K - 273.15
  • °F to °R: °F + 459.67
  • °R to °F: °R - 459.67

History of Temperature Scales

The Fahrenheit scale was developed by Daniel Gabriel Fahrenheit in 1724. The Celsius scale was created by Anders Celsius in 1742, originally with 0° as the boiling point and 100° as the freezing point, later reversed. Lord Kelvin introduced the absolute temperature scale in 1848, based on the concept of absolute zero.

Quick Tips

  • • Remember: 0°C = 32°F (water freezing point)
  • • Body temperature: ~37°C or ~98.6°F
  • • Absolute zero: -273.15°C or 0K
  • • Use Kelvin for scientific calculations