Red flames tend to be around 977 degrees Fahrenheit to about 1832 degrees (525 to 1000 Celsius) Orange flames are hotter, roughly 2012 to 2192 degrees (1100 to 1200 Celsius) White flames are even hotter, about 2372 degrees to 2732 degrees (1300 to 1500 Celsius) Blue flames are the hottest of them all and can burn as hot as 5432 degrees (3000 Celsius)