The hottest flame color is blue, often accompanied by blue-violet or violet hues. Blue flames occur in conditions of complete combustion with sufficient oxygen supply and can reach temperatures above 2,552 to 3,000 degrees Fahrenheit (1,400 to 1,650 degrees Celsius) or even higher, with some sources noting blue flames can burn as hot as 5,432 degrees Fahrenheit (3,000 degrees Celsius). Violet or blue-violet flames can indicate even hotter temperatures beyond typical blue flames. In contrast, flames that appear red, orange, or yellow are usually cooler and result from less complete combustion.
Flame Colors and Temperatures
- Blue flame: The hottest flame, signifying complete combustion, ranges roughly from 1,400 °C to as high as 3,000 °C (2,552 to 5,432 °F).
- Violet/blue-violet flame: Can be hotter than blue flame, with temperatures surpassing 3,000 °F (1,650 °C).
- White flame: Hot but typically cooler than blue, ranging from 1,300 °C to 1,500 °C (2,400 °F to 2,700 °F).
- Orange, yellow, red flames: Cooler, with red being the coolest (around 525 °C or 980 °F) and orange/yellow flames indicating incomplete combustion with moderate temperatures.
Thus, the strongest indicator of the hottest flame color is blue, often moving toward violet or blue-violet under ideal combustion conditions.
