This utility will convert a temperature for fahrenheit, celsius and Kelvin (just in case you might need Kelvin).
To convert from the temperature Fahrenheit to Celsius manually, first subtract 32, then multiply by 100/180, or Deduct 32, then multiply by 5, then divide by 9.
To convert from the temperature Celsius to Fahrenheit manually, first multiply by 180/100, then add 3; or Multiply by 9, then divide by 5, then add 32.