Free fuel cost calculator
Enter distance, your car's mpg, and gas price — this fuel cost calculator shows trip cost and annual fuel spend in seconds, updated live, as you type.
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Actual fuel consumption depends on driving style, terrain, and vehicle condition. EPA ratings are for comparison only.
Results are estimates. Consult a professional.
How the fuel cost calculator works
This calculator converts trip or annual distance into a fuel cost using your vehicle's fuel economy (mpg) and the local price per gallon. The math is straightforward: divide total miles by fuel efficiency to find gallons consumed, then multiply by the price per gallon to get the total cost.
The EPA publishes combined, city, and highway mpg ratings for every new vehicle. Combined mpg (55% city / 45% highway) is the best single figure for mixed driving. Real-world mpg typically runs 15–20% below the EPA label, especially in cold weather, stop-and-go traffic, or at highway speeds above 65 mph. Using the EPA combined figure for trip planning provides a reasonable — if slightly optimistic — estimate.
EPA fueleconomy.gov — official source for US vehicle mpg ratingsWorked example: annual fuel cost for a 28 mpg sedan
Driver profile: Average US driver, 13,500 miles/year (FHWA 2023). Vehicle: mid-size sedan, EPA combined 28 mpg. Fuel: regular unleaded at $3.50/gallon.
Annual fuel cost by mpg and price per gallon
The table below shows annual fuel costs at the US average of 13,500 miles per year. Find your vehicle's mpg column, then read across to your local gas price row for a quick estimate.
| Price/Gallon | 25 mpg | 30 mpg | 35 mpg | 40 mpg |
|---|---|---|---|---|
| $3.00/gal | $1,620 | $1,350 | $1,157 | $1,013 |
| $3.50/gal | $1,890 | $1,575 | $1,350 | $1,181 |
| $4.00/gal | $2,160 | $1,800 | $1,543 | $1,350 |
| $4.50/gal | $2,430 | $2,025 | $1,736 | $1,519 |
Source: EPA fueleconomy.gov, AAA 2024, FHWA 2023; assumes 13,500 miles/year.
Tips to reduce your fuel costs
Small changes in driving habits and vehicle maintenance can meaningfully cut fuel spending without changing your vehicle. The AAA estimates that poor maintenance and aggressive driving habits can reduce real-world mpg by 15–30%.
- Maintain proper tire pressure — Under-inflated tires increase rolling resistance. The DOE estimates that each PSI drop below recommended pressure reduces mpg by about 0.2%. Check monthly; pressure drops ~1 PSI per 10°F temperature decrease.
- Slow down on the highway — Aerodynamic drag increases with the square of speed. Driving 75 mph instead of 65 mph can cut fuel economy by 15–20%, adding hundreds of dollars per year for highway-heavy commuters.
- Use cruise control on flat highways — Steady-speed driving beats the natural speed oscillation of manual throttle inputs. AAA testing shows 7–14% mpg improvement on flat interstate routes.
- Track gas prices with GasBuddy or AAA — Prices at nearby stations can vary by $0.20–$0.40/gallon in the same ZIP code. Filling up at the cheapest station adds up: a $0.25/gallon savings on 500 gallons/year = $125.
- Consider mpg when buying, not just payment — A vehicle with 10 mpg better fuel economy saves $450–$800/year at current prices. Over five years, that's $2,250–$4,000 — often more than the payment difference between trim levels.
Accuracy and limitations
EPA mpg figures are measured under controlled laboratory conditions and consistently run higher than real-world results. The EPA itself notes that actual mpg will vary based on driving speed, traffic, weather, payload, and use of air conditioning. For planning purposes, multiplying the EPA combined figure by 0.85 gives a more realistic real-world estimate — especially for older vehicles, trucks, or turbocharged engines.
Gas prices are highly volatile and differ by region, season, and grade. The US average cited in this tool (~$3.40/gallon regular, AAA 2024) is a national midpoint; California, Hawaii, and the Pacific Northwest typically run $0.50–$1.50 above average, while the Gulf Coast and Midwest often run below. Enter your local price from GasBuddy.com or AAA's daily fuel gauge for the most accurate result.
Fuel economy terms defined
About this fuel cost calculator
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