Gas Cost Calculator
Work out the gas cost of a one-off trip, your daily commute, or your annual mileage. Enter the distance in miles, your vehicle's MPG, and the current pump price in dollars per gallon — the calculator returns the cost. EV drivers can switch to a per-mile electricity figure based on their utility rate and home-charging efficiency.
How is this calculated?
Gallons used = miles ÷ MPG. Cost = gallons × price per gallon. Pump prices are quoted per U.S. gallon (3.785 liters). For EVs, energy used = miles × kWh-per-mile (typically 0.25–0.35 for most U.S. EVs in real-world conditions), then multiplied by your electricity rate in cents per kWh. DC fast charging at public stations is materially more expensive than home charging on a residential rate or off-peak time-of-use plan.
Frequently Asked Questions
How do I find my car's true MPG?
EPA window sticker figures are useful for comparison but routinely 10%–20% higher than real-world. Calculate your own by filling the tank, recording the trip mileage, and dividing miles traveled by gallons pumped on the next refill. Most modern vehicles also display a rolling lifetime average in the dashboard.
Are EVs cheaper to run?
Significantly, if you charge at home — running costs are often 3–5 cents per mile compared with 12–18 cents per mile for a gasoline equivalent. Public DC fast charging at 40–60 cents per kWh narrows the gap considerably, so home charging access is the real swing factor. Federal and state EV incentives can also reduce upfront cost.
How much federal and state tax am I paying on gas?
Federal gas tax is 18.4 cents per gallon (24.4¢ on diesel). State gas taxes range from around 9¢ in Alaska to over 60¢ in California. Some states also apply sales tax on top. The IRS publishes federal rates; state DOTs publish state-level rates. Together, taxes typically account for 15%–25% of the pump price.
Does driving style really make a difference?
Yes — typically 10%–25%. Steady highway speeds (60–65 mph rather than 75+), gentle acceleration, anticipating lights, properly inflated tires, and not lugging around an empty roof rack all add up. Short cold-start trips are the worst case for gas cars; the engine never reaches efficient operating temperature.
Last updated: May 2026 · Rates sourced from IRS