What is what color is diesel fuel?

Diesel fuel's color isn't standardized and can vary depending on several factors, including:

• Additives: Different additives used for things like lubricity, cetane improvers, or anti-icing can affect the color. These additives are often dyed themselves.
• Source of Crude Oil: The crude oil from which the diesel is refined can influence its base color.
• Refining Process: Variations in the refining process can also slightly alter the color.

Generally, diesel fuel ranges in color from clear to a very dark amber or even brownish-red. It's often described as a straw color to a dark yellow-brown. You will rarely see it completely clear unless it's highly refined or a particular type designed for specific applications. The color itself is not a reliable indicator of quality or performance. Rather than relying on color, proper testing using standardized methods is necessary to assess fuel quality.