Is 87 octane a regular gas?
Yes. In the United States, 87 octane is the standard regular gasoline grade sold at most stations.
Globally, octane ratings are measured on different scales and labeled differently. The key point for drivers is to use the octane level recommended by the vehicle’s manufacturer, which is commonly printed in the owner's manual or on a sticker inside the door jamb.
What octane means
Octane measures a fuel’s resistance to knocking in an internal combustion engine. The higher the octane, the more resistant the fuel is to pre-ignition under pressure. There are different scales: AKI (used by the United States) and RON (used in many other countries). A number on one scale does not map directly to the same number on the other.
- AKI vs RON: AKI is roughly 1–2 points lower than RON for the same fuel blend, so 87 AKI may correspond to about 91–92 RON in some markets, but it varies by blend.
- Fuel grades: Regular sits at the low end of the octane spectrum, followed by mid-grade and premium, with higher octane used for engines prone to knocking or designed for high compression.
- Role of ethanol: In the U.S., regular gasoline is commonly sold as 87 AKI with up to 10% ethanol (E10). The ethanol content can affect energy content and octane slightly.
Understanding these basics helps explain why 87 octane is considered regular in one market but not universally across all regions.
87 octane and the U.S. regular grade
In practice, 87 octane is the baseline fuel grade for most passenger cars in the United States. It is the standard option at many stations and is often blended with ethanol. Vehicles designed for regular gasoline typically require 87 octane or higher; engines with higher compression or turbocharging may specify higher-octane fuels to prevent knocking.
Higher octane: when it matters
Using a higher-octane fuel than what your engine requires does not automatically increase power or fuel economy. It is only beneficial for engines that are designed to operate with higher octane or under conditions that promote knocking (like high loads, high temperatures, or high compression). If your owner’s manual specifies 87, using premium 91–93 octane generally yields no noticeable benefit.
- Check manufacturer recommendations: Use the octane level specified for your vehicle.
- Turbocharged/high-compression engines may require higher octane to prevent knocking.
- Fuel costs and benefits: Higher-octane fuels are typically more expensive and may not pay off in everyday driving without a matched engine design.
In all cases, following the manufacturer’s guidance helps ensure optimal performance and longevity of the engine.
Summary
87 octane is widely regarded as the regular gasoline grade in the United States, representing the baseline option for most everyday vehicles. Octane scales differ by region, so if you’re outside the U.S., verify local labeling and the recommended octane in your owner’s manual. Using the correct octane protects against knocking and aligns with expected performance and efficiency.
