The short answer
A 300 mile trip in a car getting 25.5 mpg, EPA's real-world average for new gas and hybrid cars, uses 11.8 gallons of gas: about $47.00 at the U.S. average of $4.00 a gallon (EIA, week of 2026-11-09). That's $0.16 a mile. A 20 mpg pickup spends $59.93, a 50 mpg hybrid $23.97.
The same trip in every state
300 miles at 25.5 mpg, at each state's latest EIA weekly gas price.
| Alabama | $40.95 |
|---|---|
| Alaska | $53.93 |
| Arizona | $53.93 |
| Arkansas | $40.95 |
| California | $65.44 |
| Colorado | $44.07 |
| Connecticut | $47.76 |
| Delaware | $48.78 |
| District of Columbia | $48.78 |
| Florida | $43.84 |
| Georgia | $42.46 |
| Hawaii | $53.93 |
| Idaho | $46.42 |
| Illinois | $45.51 |
| Indiana | $45.51 |
| Iowa | $45.51 |
| Kansas | $45.51 |
| Kentucky | $45.51 |
| Louisiana | $40.95 |
| Maine | $47.76 |
| Maryland | $48.78 |
| Massachusetts | $47.14 |
| Michigan | $45.51 |
| Minnesota | $45.28 |
| Mississippi | $40.95 |
| Missouri | $45.51 |
| Montana | $46.42 |
| Nebraska | $45.51 |
| Nevada | $53.93 |
| New Hampshire | $47.76 |
| New Jersey | $48.78 |
| New Mexico | $40.95 |
| New York | $48.42 |
| North Carolina | $42.46 |
| North Dakota | $45.51 |
| Ohio | $44.33 |
| Oklahoma | $45.51 |
| Oregon | $53.93 |
| Pennsylvania | $48.78 |
| Rhode Island | $47.76 |
| South Carolina | $42.46 |
| South Dakota | $45.51 |
| Tennessee | $45.51 |
| Texas | $40.09 |
| Utah | $46.42 |
| Vermont | $47.76 |
| Virginia | $42.46 |
| Washington | $57.34 |
| West Virginia | $42.46 |
| Wisconsin | $45.51 |
| Wyoming | $46.42 |
EIA reports weekly prices for some states and for regions; states without their own use their region's.
How it works
The formula
cost = gallons × price per gallon
Assumptions
- Gas prices are EIA's weekly regular gasoline prices: the state's own where EIA reports one, otherwise its region's. Your pump price may differ; type it in.
- The default 25.5 mpg is EPA's real-world average for model year 2024 new vehicles (27.2 mpg) less the 1.7 mpg that electric and plug-in hybrid cars add to it. Highway driving usually beats it; towing, heavy loads and speed lower it.
- Fuel only: tolls, parking and wear aren't included.
Worked example: 300 miles
- 300 ÷ 25.5 mpg = 11.76 gallons
- × $4.00 = $47.00
Ways to cut the cost
- Check your real mpg at your next fill-up: miles since the last fill ÷ gallons it took.
- Ease off the speed: fueleconomy.gov says gas mileage usually drops quickly above 50 mph.
- Fill up before crossing into a pricier state; the table shows where gas is cheapest.
Questions people ask
How do I calculate gas cost for a trip?
Divide the miles by your car's miles per gallon to get gallons, then multiply by the price of gas. A 300 mile trip at 25.5 mpg takes 11.8 gallons; at the U.S. average of $4.00 a gallon (EIA, week of 2026-11-09) that's $47.00.
What MPG should I use?
Your car's real figure is best: divide the miles since your last fill-up by the gallons it took. EPA puts the average model year 2024 new vehicle at 27.2 mpg in real-world driving, or 25.5 mpg leaving out electric and plug-in hybrid cars, the figure we start a gas car at. A pickup getting 20 mpg spends $59.93 on the same 300 miles; a 50 mpg hybrid $23.97.
What does gas cost per mile?
At $4.00 a gallon and 25.5 mpg, about $0.16 a mile, or $15.67 per 100 miles. That's fuel only; wear, tires and depreciation cost more.
Is it cheaper to drive or fly?
Add up the gas for the round trip, tolls and parking, and compare with the tickets for everyone going. For several people, driving often wins on shorter trips; the calculator gives the fuel part.