Temperature Converters
Convert Celsius to Fahrenheit, Fahrenheit to Celsius, and Kelvin conversion formulas used across engineering, weather, and science workflows. Kelvin is the SI base unit of thermodynamic temperature, and each scale uses a different zero reference tied to absolute zero.
Explanation
Temperature is a measure linked to the average kinetic energy of particles. Kelvin (K) is the SI base unit of thermodynamic temperature, and 0 K is absolute zero. Celsius is defined relative to kelvin using K = °C + 273.15, while Fahrenheit is defined relative to Celsius through a linear scale transformation. Because scales differ in both interval size and zero reference, conversions require both a multiplicative factor and an additive offset. Unlike most other hubs, temperature conversions are not purely multiplicative. For clarity, all temperature conversions in this hub are implemented using exact affine transformation formulas.
Temperature pages are organized by conversion direction so mirror leaves remain aligned and comparable.
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Open a family hub to reach leaf pages with direct answers, calculator output, and reverse links built on the same constants.
Frequently Asked Questions
Why is temperature not a simple multiply?
Different scales use different zero points and interval sizes, so each conversion needs both scaling and offset terms.
What is absolute zero?
Absolute zero is 0 K, the thermodynamic lower limit where classical thermal motion is minimized.
Why can Kelvin not be negative physically?
Kelvin is an absolute thermodynamic scale anchored at 0 K, so negative values are not physically valid for standard thermodynamic states.
Why is 273.15 used?
It is the exact offset between Celsius and Kelvin, defined by K = °C + 273.15.
How do I switch direction?
Use Switch Units to navigate to the mirror page for the reverse formula.