E10 vs E15 Gasoline

E10 contains up to about 10 percent ethanol by volume. E15 contains 10.5 to 15 percent ethanol. The difference sounds small, but compatibility rules matter.

E10

E10 is widely used in gasoline vehicles and is compatible with the broadest range of modern gasoline-powered equipment.

E15

EPA allows E15 for model year 2001 and newer light-duty conventional vehicles. It is not approved for every engine or fuel system, including certain motorcycles, boats, and small engines.

Energy content differs

Ethanol contains less energy per gallon than gasoline. A higher ethanol blend can produce a small fuel-economy difference depending on the vehicle and conditions.

Check the pump and owner's manual

Use the fuel the vehicle or equipment manufacturer approves. Pump labels identify E15, and small-engine equipment often has stricter fuel guidance.

Quick checklist

Use the product label, manufacturer directions, and the specific requirements of your situation. Compare the complete product or system rather than making a decision from one marketing phrase, ingredient, or number.