Absolute zero is 0 on the Kelvin scale and -273.15 degrees Celsius.
Note: Since 1967, the term "degree" has not been used for Kelvin temperature measurements. It is used with measurements on the Fahrenheit and Celcius scales. This is basically because the "Kelvin" is the unit of measurement and saying "degrees" would be redundant. This is not true for the F and C scales.