The color of radiator fluid, also known as antifreeze or coolant, can vary depending on the type of formulation and manufacturer. The most common colors of antifreeze are green, orange, red, purple, blue, yellow, and pink. The color of antifreeze is not an indicator of its chemical composition or effectiveness. Fresh antifreeze is usually clear and brightly colored, with colors ranging from blue, red, green, violet, yellow, or orange. However, the color of antifreeze can change over time due to contaminants, rust, or other factors. Therefore, it is important to check the owners manual or consult a professional to determine the appropriate type of antifreeze for a specific vehicle, rather than relying on the color of the fluid.