If you want to find out the conversion of kelvin to celsius, do not use Google. A Google search for [kelvin to celsius] returns the wrong calculation. Google returns 1 kelvin = -272.15 degrees Celsius.
This issue was brought up in a Google Web Search Help thread. Since I do not know the first thing about these types of conversions, I decided to see what Wolfram Alpha had to say about the calculation. The same search on Wolfram returns the correct calculation:
272.15 is wrong, but 273.15 is correct.
Forum discussion at Google Web Search Help.