The average fuel efficiency of a car in 2026 is expected to be around 30 miles per gallon (mpg), assuming a standard vehicle. This means that a full tank of gas, which is typically around 15 gallons, would last approximately 450 miles. This estimate is based on the current trends in automotive technology and fuel economy standards set by the Environmental Protection Agency (EPA).

The reason for this estimate lies in the ongoing advancements in automotive engineering and the increasing emphasis on fuel efficiency. The EPA has set stringent fuel economy standards for new vehicles, which have led to the development of more efficient engines and vehicles. For instance, electric vehicles (EVs) are becoming more prevalent, offering an alternative to traditional gasoline-powered cars. While EVs do not rely on gasoline, they have a significant impact on the overall fuel efficiency of the automotive market.

According to the EPA, the average fuel economy for new vehicles in the United States has improved from around 27.5 mpg in 2010 to approximately 33 mpg in 2020. This upward trend is expected to continue, with the average fuel efficiency reaching around 35 mpg by 2026. This increase in fuel efficiency is a result of several factors, including:

1. Advanced Engine Technology: Modern engines are more efficient, thanks to improvements in combustion processes, turbocharging, and direct fuel injection.

2. Lightweight Materials: Vehicles are being made with lighter materials, such as aluminum and high-strength steel, which reduce the overall weight and improve fuel efficiency.

3. Regulatory Standards: The EPA's Corporate Average Fuel Economy (CAFE) standards have been a driving force behind the push for more fuel-efficient vehicles.

4. Alternative Fuel Vehicles: The increasing popularity of EVs and other alternative fuel vehicles is also contributing to the overall improvement in fuel efficiency.

It is important to note that these estimates can vary depending on the specific make and model of the vehicle, driving conditions, and individual driving habits. For example, a vehicle with a higher fuel efficiency rating may have a longer range on a full tank of gas, while a vehicle with a lower rating may have a shorter range. Additionally, factors such as traffic congestion, weather conditions, and road conditions can also affect fuel efficiency and range.

In conclusion, the average fuel efficiency of a car in 2026 is expected to be around 30 mpg, resulting in a range of approximately 450 miles per full tank of gas. This estimate is based on current trends in automotive technology and fuel economy standards set by the EPA. As the automotive industry continues to evolve, these numbers may change, but the overall trend is clear: vehicles are becoming more fuel-efficient, leading to longer ranges and reduced environmental impact.