Temperature Converter
Convert any temperature between Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R) instantly.
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Frequently Asked Questions
What is the formula to convert Celsius to Fahrenheit?
°F = (°C × 9/5) + 32. To go the other way: °C = (°F − 32) × 5/9. The -40 point is special — it’s the same in both scales (-40°C = -40°F).
What is Kelvin and when is it used?
Kelvin is the SI unit for thermodynamic temperature, starting at absolute zero (the coldest possible temperature, −273.15°C). Used in science, physics, and astronomy. There are no negative Kelvin temperatures.