Calculate MPG or estimate fuel costs for any trip
To accurately measure your fuel economy, fill your tank completely and reset your trip odometer. Drive normally until you need fuel again. Fill up completely again and note the gallons used. Divide the trip miles by the gallons to get your MPG. Repeat a few times for a reliable average.
Driving habits (aggressive driving lowers MPG by 15-33% on highways), vehicle maintenance (under-inflated tires reduce MPG by 0.2% per PSI), weather (cold weather reduces efficiency), cargo weight, and fuel quality all impact your gas mileage.
Keep tires properly inflated, avoid excessive idling, use the recommended grade of motor oil, remove unnecessary weight from your vehicle, plan trips to combine errands, and maintain a steady speed on the highway using cruise control.