Vehicle Tools
Road Trip Fuel Cost Calculator
Fuel cost can swing a trip budget, especially when prices change or you add detours. This calculator estimates gallons and cost using distance, MPG, fuel price, round-trip selection, and extra miles.
Planning note
How this calculation works
- Gallons are estimated as total miles divided by vehicle MPG.
- Cost is gallons multiplied by fuel price per gallon.
- Extra miles are added to the selected trip distance so detours, errands, or scenic stops are included.
Assumptions and limitations
- Your actual MPG can change with traffic, speed, elevation, weather, towing, roof racks, tire pressure, and heavy loads.
- Fuel prices vary by location and date.
- This tool does not include tolls, parking, maintenance, depreciation, or lodging.
Worked example
A 300 mile trip at 25 MPG and $3.60 per gallon uses about 12 gallons one way, or about $43.20 before extra miles.
FAQ
Should I use city, highway, or combined MPG?
Use the number that best matches your trip. Highway MPG may fit open-road trips, while combined MPG may fit mixed driving.
How do towing or cargo affect this?
Towing, roof cargo, and heavy loads can reduce MPG substantially, so consider lowering the MPG input.
Does round trip double everything?
The tool doubles the entered trip distance when round trip is selected, then adds any extra miles allowance.
Can I use this for electric vehicles?
This version is built for gasoline or diesel MPG. An EV charging cost tool would use kWh per mile and charging cost instead.