Is there really a difference between unleaded and premium?
Daniel Moore
Published Jan 14, 2026
The premium octane is usually going to sit at around 91, while the regular gasoline is right around 85 to 87. In terms of actual energy produced, including improved MPG, there is actually no real difference between unleaded and premium.
Is there a big difference between unleaded and premium gas?
The main difference between Unleaded and Premium is that they have different levels of octane in their chemical composition. Unleaded petrol has a lower octane quantity and rating while Premium petrol has a comparatively higher octane level in its composition as well as chemical structure, which set these two apart.
Is it worth getting premium unleaded?
It is perfectly fine to use a higher-octane fuel than the manufacturer recommends for your car – though it's unlikely to offer any discernible benefit. The only guarantee is that it'll cost you more.
What happens if I put premium gas instead of unleaded?
Putting Regular Fuel in a Car That Requires Premium
Using lower octane fuel in a vehicle that requires premium gas could cause some serious internal damage. You'll most likely notice the spark knock (a sort of high-pitched pinging or rattling noise).
Is it OK to use premium gas instead of regular?
Typically, "regular" gas is 87 octane, while anything over 91 octane is considered "premium" gasoline. A spokesperson with the American Automobile Association told FOX Business that it is safe to use premium fuel in your vehicle even if it takes regular.
18 related questions foundCan you use premium gas in a regular car?
That said, putting premium gas in a regular car won't hurt it. But you'll certainly spend more per gallon, and your regular car won't get better fuel economy with high-octane fuels. Ideally, any car with a high-compression engine or parts, or even turbochargers, deserves premium gasoline.
Does premium unleaded last longer?
Premium on the other hand ups the octane rating to 97, 98 or even as high as 99. That means it will burn a little more efficiently and powerfully and just as a candle burns more brightly when supplied with more oxygen, so does the fuel in your car's engine.
Why is premium unleaded more expensive?
Most standard unleaded fuels have a 95-octane rating, but premium fuel has a higher rating (around 98-octane) but is more expensive to produce, hence the higher price.
Does premium gas last longer than regular gas?
Sadly, there's nothing in premium gasoline that would make it last longer than other fuels from the pump. Since the distinguishing feature is the higher-octane levels, the only real benefit you gain is lowering the chance of engine knocking, which isn't much of a threat on most modern fuel systems.
What is the best gas to put in your car?
Regardless of whether your car calls for regular or premium, the best choice for ongoing performance and economy is a TOP TIER gasoline. Recent AAA testing found TOP TIER gasolines keep internal engine components up to 19 times cleaner than gasolines that only meet minimum EPA standards.
Is unleaded gas bad for your car?
“Use premium unleaded gasoline with a posted octane rating of 91 or higher. If the octane rating is less than 91, you could damage the engine and may void your vehicle warranty.
Is premium gas a waste of money?
Americans Waste HOW Much Money on Premium Gas?!
According to AAA, you're wasting money every time you fill up with premium if your owner's manual recommends regular. Apparently, Americans are wasting $2.1 billion a year buying premium gasoline when their cars only need regular.
Will premium gas clean my engine?
Nope. Regular, plus, and premium gas all come with detergents to mitigate against carbon deposits in your engine. Plus and premium don't come with special powers for cleaning out the engine. If you're interested in cleaning out your engine, you're better off taking it in for service.
Does premium gas burn slower?
Fuel with an 87 octane rating burns more quickly while higher-octane fuels burn more slowly. In engines designed for standard unleaded fuel, efficiency and performance is optimized for 87 octane and could actually perform worse with higher-octane fuel since the burn rate is slower.
Which gas last the longest?
93 octane fuels are more refined and contain more stable hydrocarbons. These stable hydrocarbons can last 2-3 times longer than 87 octane fuel. Even in proper storage 87 octane gas can start to degrade in 3 months, 93 octane fuel should last closer to 9 months before degradation is noticeable.
Why do some cars need premium gas?
Why do some cars require premium gas? Premium gas — that is, gas with an octane rating of 91 or more — is required for some high performance and luxury vehicles. Gasoline with a high octane rating is more difficult to ignite, which helps prevent pre-ignition and knocking in high performance engines.
Is unleaded or super unleaded better?
Super-unleaded petrol can sustain a higher pressure before burning than standard petrol, essentially allowing the engine to produce slightly more power. Super-unleaded burns a little more efficiently than standard petrol, and also helps to prevent pre-ignition in the engine.
Is it good to use premium gas once in awhile?
Premium gas 90-93 is completely okay to put in a standard vehicle. Car experts say there is no risk of damage to a standard car using premium fuel.
Why is premium gas so expensive?
Smarter engines protect themselves
That's one reason premium costs more. To increase the octane rating and reduce knock, refineries use a more elaborate process that blends an expensive substance called alkylate into the fuel.
What vehicles require premium gas?
- Audi A3; 2.0-liter turbo four.
- Audi Q3; 2.0-liter turbo four.
- Audi TT; 2.0-liter turbo.
- Cadillac XT5; 3.6-liter V6.
- Cadillac XT6; 3.6-liter V6.
- Lexus ES; 2.5-liter hybrid four; 3.5-liter V6.
- Lexus NX; 2.5-liter four.
- Lexus RX; 3.5-liter V6.
How much more is premium unleaded?
Premium fuels will often cost up to 10p more per litre to fill up with compared to standard fuels.
Where is the cheapest fuel in the world?
Venezuela is the world's cheapest country to buy petrol, where amazingly it costs just 2 pence (GBP) a litre. This is because it's home to some of the biggest oil reserves in the world. But it's also a country where income is very low too.
Does premium gas cost more to make?
Q: Why does premium gas cost so much more than regular? A: According to a U.S. Department of Energy website on fuel economy, the fuel components that boost octane are generally more expensive to produce.
What happens if you put 93 instead of 87?
In addition to 95 octane fuel running through the 87 or 89 octane engines, you have absolutely no harm to your engine. The 93 octane fuel will not need to be run in any circumstances. In fact, it won't improve how your car runs. The fuel does not get better with it.
Is premium gas Really Better?
The main difference with premium is its octane rating — 91 or higher compared with 87 for regular octane. The higher octane gives premium gas greater resistance to early fuel ignition, which can result in potential damage, sometimes accompanied by audible engine knocking or pinging.