Calculator guide
Estimate fuel required and fuel cost from trip distance, vehicle fuel economy, and price per gallon.
Formula or method
Gallons = miles ÷ miles per gallon; fuel cost = gallons × price per gallon; cost per mile = fuel cost ÷ miles.
How to use this calculator
- Enter one-way or total trip distance as intended.
- Enter the vehicle's miles per gallon and current fuel price.
- Review gallons, total cost, and cost per mile; use round-trip distance when appropriate.
Worked example
A 300-mile trip at 28 MPG uses about 10.71 gallons; at $3.50 per gallon, fuel costs about $37.50.
Understanding the result
This isolates fuel expense. Real-world economy can vary with speed, traffic, weather, load, and driving style.
Limitations and assumptions
- Excludes tolls, parking, maintenance, depreciation, electricity, and fuel-price changes.
- Zero or negative MPG cannot produce a meaningful estimate.
Frequently asked questions
Should I use EPA MPG?
Use a realistic observed average when available; your actual economy may differ from the rating.
Does it include a return trip?
Only if the distance you enter includes it.
Can I compare two cars?
Yes, run the same distance and fuel price with each vehicle's economy.
Sources
Educational information only; verify important decisions with a qualified professional.