Converter category
Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, Rankine, Réaumur, Delisle, and Newton temperature scales.
Universal Temperature Converter
About temperature conversions
Temperature conversions are needed every day, from checking the weather and setting an oven to running scientific experiments and monitoring health. Our temperature converter handles Celsius, Fahrenheit, Kelvin, Rankine, Réaumur, Delisle, and Newton scales. It uses the exact formulas defined for each scale, so you can convert confidently for cooking, travel, education, engineering, and research. Simply enter the value, choose the source scale, and see the result in every supported scale instantly.
Most popular temperature conversions
Available units
Popular temperature conversions (9 total)
Unit definitions
Celsius (°C)
Celsius is a temperature scale where 0°C is the freezing point of water and 100°C is the boiling point at sea level.
Origin: Developed by Swedish astronomer Anders Celsius in 1742. Originally had 0° as boiling and 100° as freezing, reversed after his death.
Current use: Weather reporting, Cooking, Scientific research
Fahrenheit (°F)
Fahrenheit is a temperature scale where 32°F is the freezing point of water and 212°F is the boiling point at sea level.
Origin: Developed by German physicist Daniel Fahrenheit in 1724. He set 0° as the coldest temperature he could create (salt and ice mixture).
Current use: Weather (US), Cooking (US recipes), Industrial processes
Kelvin (K)
Kelvin is the SI base unit of temperature. 0 K (absolute zero) is the coldest possible temperature where molecular motion stops.
Origin: Named after William Thomson, 1st Baron Kelvin. Defined so that triple point of water is exactly 273.16 K.
Current use: Scientific research, Astrophysics, Thermodynamics
Rankine (°R)
Rankine is an absolute temperature scale using Fahrenheit degrees. 0°R is absolute zero (−459.67°F).
Origin: Named after William John Macquorn Rankine, a Scottish engineer and physicist.
Current use: Thermodynamics (US engineering), Steam engine calculations
Réaumur (°Ré)
Réaumur scale: water freezes at 0°Ré, boils at 80°Ré.
Origin: Developed by René-Antoine Ferchault de Réaumur in 1730.
Current use: Historical (Europe), Food processing, Cheese making
Delisle (°De)
Delisle scale: water freezes at 150°De, boils at 0°De.
Origin: Developed by Joseph-Nicolas Delisle in 1732.
Current use: Historical (Russia), Thermometry
Newton (°N)
Newton scale: water freezes at 0°N, boils at 33°N.
Origin: Developed by Isaac Newton around 1701.
Current use: Historical science, Thermodynamics
Common uses for temperature conversions
Temperature conversions are used in weather reports, oven and cooking instructions, medical readings, scientific experiments, HVAC systems, and international travel.
Frequently asked questions about temperature
How do you convert Celsius to Fahrenheit?+
Multiply Celsius by 1.8 and add 32. For example, 20°C = 68°F.
What is the difference between Celsius and Fahrenheit?+
Celsius sets water's freezing point at 0° and boiling point at 100°. Fahrenheit sets them at 32° and 212°. Celsius is used in most countries; Fahrenheit is common in the US.
What is Kelvin used for?+
Kelvin is the SI base unit for temperature and is used in science, physics, and astronomy where absolute zero is the reference point.