Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, and Rankine temperature scales.

Conversion Result

20 °C (Celsius)

68

°F (Fahrenheit)

🌡️ Reference Points

Freezing (water): 0°C = 32°F = 273.15K

Room temp: 20°C = 68°F = 293.15K

Body temp: 37°C = 98.6°F = 310.15K

Boiling (water): 100°C = 212°F = 373.15K

Quick Tips

Rough conversion: °F ≈ °C × 2 + 30

Accurate formula: °F = (°C × 1.8) + 32

Celsius is metric and used worldwide except USA

Kelvin: No degree symbol, used in science

How to Use the Temperature Calculator

Enter a temperature value, select the current scale (Celsius, Fahrenheit, Kelvin, or Rankine), choose your target scale, and the conversion displays instantly. Essential for cooking, science, and weather.

Formula

Celsius ↔ Fahrenheit: °F = (°C × 9/5) + 32
Celsius ↔ Kelvin: K = °C + 273.15
Rankine: °R = (°C + 273.15) × 9/5

History & Interesting Facts

💡 Did You Know?

Absolute zero (−273.15°C, −459.67°F, 0K) is the lowest possible temperature in the universe, where all molecular motion theoretically stops.

Origin & History

Celsius (1742): Named after Anders Celsius, water freezes at 0°C and boils at 100°C. Fahrenheit (1724): Named after Daniel Fahrenheit, uses water 32°F-212°F. Kelvin: SI unit, absolute zero at 0K.

Fascinating Facts

  • 1

    Room temperature is typically 20-25°C (68-77°F)

  • 2

    Body temperature is 37°C (98.6°F)

  • 3

    Water boils at 100°C (212°F) at sea level

  • 4

    The formula for Celsius to Fahrenheit: multiply by 1.8, then add 32

  • 5

    Kelvin is used in science because it has no negative values

  • 6

    Rankine is rarely used except in engineering

Frequently Asked Questions

What is absolute zero?

Absolute zero is the lowest possible temperature: −273.15°C, −459.67°F, or 0K. All molecular motion theoretically stops here.

Why is Kelvin used in science?

Kelvin is the SI unit of temperature. It starts at absolute zero and has no negative values, making calculations and ratios simpler.

What is room temperature?

Room temperature is typically 20-25°C (68-77°F), which is 293-298K. It varies by location and preference.