What is the difference between Celsius and Fahrenheit?

Celsius and Fahrenheit are two temperature scales with different reference points. Water freezes at 0°C (32°F) and boils at 100°C (212°F). Celsius is the metric standard, while Fahrenheit is commonly used in the US.

What is Kelvin and why is it important?

Kelvin is the SI unit of temperature used in science and engineering. It starts at absolute zero (−273.15°C) and is used in physics and thermodynamics because it has no negative values.

What are the Réaumur and Rankine scales?

Réaumur (°Ré) sets water's freezing point at 0° and boiling point at 80°, and was widely used in Europe in the 18th–19th centuries. Rankine (°R) is an absolute scale like Kelvin but uses Fahrenheit-sized degrees, starting at absolute zero (0°R = −459.67°F); it is used in some US engineering fields.

Is there a temperature where Celsius and Fahrenheit are equal?

Yes! −40°C equals −40°F. This is the only point where both scales read the same value.

What is absolute zero?

Absolute zero is 0 Kelvin (−273.15°C, −459.67°F, or 0°R), the lowest possible temperature where all molecular motion stops.

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, Réaumur, and Rankine temperature scales with instant calculations

Convert between Celsius, Fahrenheit, Kelvin, Réaumur, and Rankine scales instantly

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