Home › Calculators › Gas Cost Calculator
Gas Cost Calculator
Find out how much fuel a trip or commute will cost, and split it fairly between everyone in the car.
The gas cost formula
Cost = Distance ÷ MPG × Price per gallon
Examples
- Road trip: 300 miles one way in a car that gets 28 mpg, with gas at $3.25, uses 10.7 gallons and costs $34.82. The round trip is $69.64, or $23.21 each split three ways.
- Commute: 20 miles each way, 250 days a year, at 28 mpg and $3.25: 10,000 miles, 357 gallons, about $1,161 a year. Switching to a 45 mpg hybrid would cut that to about $722.
Ways to use less fuel
- Drive steadily: hard acceleration and braking can cut fuel economy by 15% to 30% on the highway.
- Slow down: above about 50 mph, fuel economy drops quickly.
- Keep tires inflated to the pressure on the door sticker.
- Remove roof racks and extra weight when you aren't using them.
Weighing up a new car? Add fuel to the payment from the auto loan calculator to compare the real monthly cost.
Frequently asked questions
How do I calculate gas cost for a trip?
Divide the distance by your car's miles per gallon to get gallons, then multiply by the price per gallon. A 300-mile trip in a 28 mpg car at $3.25 a gallon uses 10.7 gallons and costs about $34.82.
How much does my commute cost a year?
A 20-mile each-way commute is 40 miles a day. At 28 mpg and $3.25 a gallon that is $4.64 a day, or about $1,160 a year over 250 working days.
What about the IRS mileage rate?
The IRS standard mileage rate covers all car costs (fuel, wear, insurance, depreciation), not just gas, so it is much higher than fuel cost alone. Use it for tax deductions and work reimbursements, not for budgeting fuel.