What is unleaded gas?

Unleaded gasoline is a type of gasoline that does not contain lead additives. Lead used to be a common additive in gasoline to improve engine performance, but it was found to be harmful to human health and the environment. Unleaded gas became widely available in the 1970s and 1980s as a safer alternative.

Unleaded gas is now the standard type of gasoline used in most vehicles around the world. It is typically designated as "regular" or "regular unleaded" at gas stations. Unleaded gas is compatible with most modern engines and reduces harmful emissions compared to leaded gasoline.

The octane rating of unleaded gas refers to its ability to resist engine knocking or pinging. The higher the octane rating, the more resistant the fuel is to combustion under pressure. Most unleaded gasoline sold at gas stations falls within the range of 87 to 93 octane, with higher octane ratings typically being used in high-performance engines.

Unleaded gas is commonly blended with ethanol, a renewable and environmentally-friendly fuel additive. This blend, known as E10 (10% ethanol and 90% gasoline), is used in many regions as a way to reduce greenhouse gas emissions and dependence on fossil fuels.