Conversion
Temperature converter
Convert any temperature between Celsius, Fahrenheit, Kelvin, and Rankine. Pick a source unit, enter a value, and see all three other scales side by side.
Formula
Celsius and Fahrenheit are everyday scales: Celsius is used almost everywhere except the United States and a few small territories; Fahrenheit dominates US weather, cooking, and HVAC. Kelvin is the SI base unit, used in physics and chemistry — it starts at absolute zero, the theoretical point of no thermal motion. Rankine is a Kelvin-style absolute scale that uses Fahrenheit-sized degrees, kept alive mostly in US engineering thermodynamics.
Conversions happen via Celsius as an intermediate: the calculator converts your input to °C, then projects out to each other scale. All conversions are linear and exact (assuming exact inputs).
Examples
- 01100 °C→ 212 °F · 373.15 K · 671.67 °R (boiling point of water)
- 020 °F→ −17.78 °C · 255.37 K · 459.67 °R
- 030 K (absolute zero)→ −273.15 °C · −459.67 °F · 0 °R
- 0498.6 °F (body temperature)→ 37 °C · 310.15 K · 558.27 °R
FAQ
- Daniel Fahrenheit (1724) calibrated 0 °F to the freezing point of a brine of water, ice, and ammonium chloride (the coldest temperature he could reproduce), and 96 °F to human body temperature (later refined to 98.6 °F). Setting 100 °F to anything other than body temperature came from later refinements when 0 and 96 weren't exactly 'right'.