Start with distance, not a promised price
The private trip workspace uses the selected corridor’s rounded one-way mileage. It is not an address-to-address distance or a return-trip quote. For gasoline, divide miles by miles per US gallon, then multiply by your price per gallon. For an EV, multiply miles by kWh per 100 miles, divide by 100, and multiply by your price per kWh.
A worked example you can change
For an illustrative 280-mile drive at 28 mpg and $3.75 per US gallon, fuel is 10 gallons or $37.50. Adding $20 for tolls and parking and $40 for other costs gives $97.50. A 10% allowance makes the planning total $107.25. These are arithmetic examples, not current route prices.
Why your real bill can differ
Fuel economy depends on how and where you drive. Use a realistic recent efficiency figure rather than assuming the best advertised figure. EV charging losses, temperature, towing, detours and different station prices can change the final amount. Our calculator does not find charging stations, validate range, quote tolls or guarantee the number of energy stops.
Compare scenarios before splitting costs
Change one assumption at a time: efficiency, energy price or other spending. The allowance applies to the complete subtotal, not just fuel. Per-person cost assumes equal sharing by the number entered. Keep the one-way trip scope consistent, and calculate a different return route separately.
Sources and further reading
US Department of Energy / EPA: fuel economy and driving ↗
Reviewed October 6, 2026. Product calculations are described separately from agency guidance.