Your Vehicle & Trip
MPG
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Fuel Cost Results
Trip Fuel Cost
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Gallons Needed (trip)—
Cost per Person—
Cost per Mile—
Annual Fuel Cost—
Monthly Fuel Cost—
Understanding Your Vehicle's True Fuel Cost
Fuel is one of the biggest variable costs of car ownership — and often underestimated. Knowing your true annual fuel cost helps you compare vehicles, evaluate commuting options, and plan road trip budgets accurately.
Factors That Affect Real-World MPG
- City vs highway driving: Most vehicles get 20–30% better MPG on the highway than in city traffic
- Speed: Fuel efficiency drops significantly above 60 mph — driving 70 vs 60 can reduce MPG by 15%
- Tire pressure: Underinflated tires increase rolling resistance and reduce MPG by 0.2% per PSI
- Air conditioning: Can reduce MPG by 5–25% in severe heat
- Vehicle age and maintenance: Dirty air filters, old spark plugs, and worn oxygen sensors reduce efficiency
The IRS Mileage Rate
For business driving, the IRS allows a standard mileage deduction of 72.5 cents per mile in 2026. This rate covers fuel, depreciation, insurance, and maintenance — not just gas.
Frequently Asked Questions
How do I find the MPG for my specific car? ▼
The EPA fuel economy rating is on every new car window sticker and available at fueleconomy.gov for all vehicles back to 1984. Your actual MPG may differ from the EPA estimate — the easiest way to track real-world fuel economy is to fill up completely, reset your trip odometer, drive until the next fill-up, then divide miles driven by gallons used.
When is an electric vehicle cheaper than gas? ▼
At average US electricity rates (~$0.16/kWh) and gas prices (~$3.40/gallon), EVs typically cost 3–5x less per mile to "fuel." On 12,000 miles per year, that can mean $1,000–$1,500 in annual fuel savings. However, the higher upfront cost and potential charging infrastructure costs affect the full break-even calculation. The federal EV tax credit (up to $7,500) also changes the math significantly.