We use standard conversion formulas: Fahrenheit = Celsius × 9/5 + 32, Kelvin = Celsius + 273.15

Absolute zero is 0 Kelvin (-273.15°C or -459.67°F), the lowest possible temperature where nothing can be colder.

Celsius is used in most countries for everyday temperatures. Fahrenheit is used in the US. Kelvin is used in science.

Yes, all temperature conversions support negative values. The tool handles absolute zero and below correctly.