Plan your road trip budget with our fuel cost calculator. Enter your trip distance, vehicle fuel efficiency (MPG), and current gas price to get total fuel cost, cost per person for splitting, and estimated CO₂ emissions.
Fuel economy is measured in miles per gallon (MPG) in the US or liters per 100 kilometers (L/100km) in most other countries. A car rated at 30 MPG uses 1 gallon of fuel for every 30 miles driven. Factors that affect real-world MPG include driving speed, terrain, weather, tire pressure, vehicle maintenance, and driving style. Highway driving typically yields 10–20% better MPG than city driving due to fewer stops and consistent speeds.
Small changes add up: maintaining proper tire pressure improves MPG by up to 3%. Removing excess weight (100 lbs reduces MPG by about 1%), driving at moderate highway speeds (55–60 mph is optimal for most cars), and avoiding aggressive acceleration all help. Carpooling or ride-sharing splits fuel costs across passengers. Over a year of commuting, even a 2 MPG improvement can save hundreds of dollars.