How to use the Gas Cost Calculator
- 1 Enter the trip distance in miles. Tick Round trip to double it.
- 2 Enter your car's MPG; use the highway figure for long drives.
- 3 Enter the gas price per gallon where you will fill up.
- 4 Read the fuel cost, gallons used and cost per person.
Worked example
300 miles at 28 MPG and $3.25 a gallon. Gallons used = 300 ÷ 28 = 10.71 gallons. Fuel cost = 10.71 × $3.25 = $34.82. As a round trip of 600 miles it is $69.64, or $34.82 each for two people sharing the drive.
Features
Round trip in one tick
Double the distance for a return journey without retyping it.
Split with passengers
Divide the fuel cost between everyone in the car.
Any vehicle
Works for cars, trucks, RVs and hybrids; just use the MPG for that vehicle.
When to use it
Moving house
Driving a rental truck at 10 MPG for 800 miles uses 80 gallons, so budget for fuel before you book the truck.
Planning a road trip
A 600-mile return trip at 28 MPG and $3.25 a gallon costs about $70 in gas.
Commuting costs
Enter your daily round trip to see what you spend on gas each day, then multiply by working days.
Choosing a car
Compare the fuel cost of a 25 MPG and a 40 MPG car over the miles you drive each year.
Frequently asked questions
How do I calculate gas cost for a trip?
Divide the distance by your car's MPG to get gallons, then multiply by the price per gallon. 300 miles ÷ 28 MPG = 10.7 gallons; at $3.25 that is $34.82.
Where can I find current gas prices?
The U.S. Energy Information Administration publishes weekly average gasoline and diesel prices by region, and apps and station signs show local prices.
Should I use city or highway MPG?
Use highway MPG for long trips on interstates and city MPG for stop-and-go driving. The combined figure is a good middle estimate.
Does this include tolls or wear?
No, only fuel. Add tolls and parking separately, and remember the IRS mileage rate includes wear and depreciation, not just gas.
Why is my real cost higher?
Speed, air conditioning, heavy loads, roof racks and hills all lower fuel economy, so real MPG is often a little below the rating.
How many gallons does my tank hold?
Most cars hold 12 to 16 gallons, and trucks and SUVs often 20 or more. Divide the trip gallons by your tank size to see how many fill-ups you need.
Is diesel cheaper per mile?
Diesel often costs more per gallon, but diesel vehicles usually get higher MPG, so the cost per mile can be similar or lower. Enter each to compare.
Results are estimates based on the official rates linked above. Confirm important figures with the issuing authority or a qualified adviser before you act on them.
Reviewed by ToolsUnlocked Team · Last updated