Trip fuel cost calculator
Driving gently at or below the speed limit can improve mileage by 10% or more, according to fueleconomy.gov. The second figure shows what a 10% improvement would save.
Get the car ready
- Tire pressure set to the door-jamb sticker, and tread checked (penny test)
- Oil changed or checked, with enough life left for the trip (maintenance guide)
- No brake warning signs: squealing, grinding, pulsing (brakes guide)
- Wipers, washer fluid, lights and coolant checked
- Roof box only if you really need it: it can cost 10% to 25% in mileage at Interstate speeds
- Roadside assistance card and a phone charger in the glovebox
Book the rest for less
We run a family of travel sites built for exactly this:
- Rooms Cheap: hotel deals in hundreds of U.S. cities
- 101 Things to Do in the USA: tours, attractions and experiences across the country
- See and Do the USA: what to see and do, state by state
- Best of the USA: top-20 lists of the best places and experiences
- 101 Things to Do in Florida: Florida attractions and day trips
- 101 Things to Do in California: Pacific Coast Highway and California attractions
Fly, then drive
For a long trip it can be cheaper, and much faster, to fly to the start and rent a car there. Check fares on Airfares for Less and compare rentals below. If you are driving to the airport, booking airport parking ahead usually beats the drive-up rate.
Your car or a rental?
A long road trip adds wear: tires, brakes, oil changes and depreciation, on top of gas. For a big trip in an older or thirsty car, a rental with unlimited mileage can be the cheaper, more comfortable option. Compare the total cost of each, and check whether your own car insurance or credit card covers rentals before paying for extra coverage.
Rental cars and airport parking
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Discover Cars
Compares rental car prices from many companies in one search, in the U.S. and abroad.
Compare rentals →AirportRentalCars.com
Searches airport rental cars across major brands, with deals for pickup at your arrival airport.
Search airport rentals →AirportParking.com
Book parking near the airport in advance, often for less than the airport's own lots.
Find airport parking →AAA
Roadside assistance for the trip, plus member discounts on hotels and attractions.
Learn about AAA →Frequently asked questions
How do I estimate gas cost for a road trip?
Divide the total miles by your car's highway MPG to get gallons, then multiply by the price per gallon. The calculator above does it for you. Add 10% for detours and city driving.
Is it cheaper to rent a car for a road trip?
Sometimes. If your car gets poor mileage or has high miles, a fuel-efficient rental with unlimited mileage can cost less once you count wear and tear. Compare the totals.
What speed saves the most gas on a road trip?
Mileage usually drops quickly above 50 mph. On the highway, driving 65 instead of 75 can make a real difference over hundreds of miles.