Mileage Calculator
Estimate trip mileage, driving time and fuel cost for any route based on distance, average speed and vehicle MPG.
How to use the Mileage Calculator
- Enter your inputs into the Mileage Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The trip calculations
Time = Distance / Speed · · · Fuel needed = Distance / MPG · · · Fuel cost = Fuel needed × Price
Simple distance/speed/cost arithmetic. Add 10–20% time buffer for traffic, rest stops and arrival logistics on longer trips.
Worked example
600-mile trip at 65 MPH average: time ≈ 9.2 hours. In a 30 MPG car at $4.20/gal: fuel ≈ 20 gal × $4.20 = $84. Add ~2 hours for fuel/food stops on a long trip.
Frequently asked questions
How realistic is "average speed"?
Highway average rarely exceeds posted limit + 5 mph including stops. For multi-hour trips, planning at 60–65 MPH average is realistic for most US interstates.
Should I use highway MPG?
For long trips dominated by highway driving, yes. EPA combined for mixed driving. Real-world tends to run 10–15% below EPA.
What about toll costs?
Not included in basic mileage calculations. Significant on some routes (Northeast Corridor, Florida, Illinois) — easily $20–50+ on multi-hour trips through toll-heavy areas.