Convert between the three major temperature scales instantly.
Celsius to Fahrenheit: °F = (°C × 9/5) + 32
Fahrenheit to Celsius: °C = (°F - 32) × 5/9
Celsius to Kelvin: K = °C + 273.15
This calculator is most useful when precision matters: technical specifications, recipe scaling, scientific measurements, or any context where an approximate conversion introduces real risk.
The most common conversion error is using an approximate factor recalled from memory rather than the exact conversion constant. For high-precision work, even small rounding differences in the conversion factor compound when applied to large values.
A UK architect receives a specification from a US client with dimensions in feet and inches. Converting each measurement to millimetres with precision ensures the drawings are accurate — approximate mental conversion would introduce errors that compound across multiple linked dimensions.
-40°C = -40°F. This is the only temperature where Celsius and Fahrenheit are equal.
100°F = 37.78°C.
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