Free Gas Cost Calculator
This gas cost calculator works out the fuel cost of any trip from its distance, your car’s MPG and the local gas price.
How the fuel cost calculator works
Fuel cost = distance ÷ MPG × price per gallon. Switch to round trip to double the distance. The cost per mile (price ÷ MPG) is handy for comparing cars or splitting costs with passengers.
Trip fuel cost by MPG (at $3.25 a gallon)
| MPG | 100 mi | 250 mi | 500 mi | 1,000 mi | Per mile |
|---|---|---|---|---|---|
| 20 mpg | $16.25 | $40.63 | $81.25 | $162.50 | $0.163 |
| 25 mpg | $13.00 | $32.50 | $65.00 | $130.00 | $0.130 |
| 30 mpg | $10.83 | $27.08 | $54.17 | $108.33 | $0.108 |
| 35 mpg | $9.29 | $23.21 | $46.43 | $92.86 | $0.093 |
| 40 mpg | $8.13 | $20.31 | $40.63 | $81.25 | $0.081 |
| 50 mpg | $6.50 | $16.25 | $32.50 | $65.00 | $0.065 |
Yearly and monthly gas cost
| MPG | 10,000 mi/yr | 12,000 mi/yr | 15,000 mi/yr |
|---|---|---|---|
| 20 mpg | $1,625 $135/mo | $1,950 $163/mo | $2,438 $203/mo |
| 25 mpg | $1,300 $108/mo | $1,560 $130/mo | $1,950 $163/mo |
| 30 mpg | $1,083 $90/mo | $1,300 $108/mo | $1,625 $135/mo |
| 35 mpg | $929 $77/mo | $1,114 $93/mo | $1,393 $116/mo |
| 40 mpg | $813 $68/mo | $975 $81/mo | $1,219 $102/mo |
| 50 mpg | $650 $54/mo | $780 $65/mo | $975 $81/mo |
Gas prices in the tables are an example ($3.25 a gallon). Prices vary by state and week, so type your own price into the calculator.
Road trip, round trip and commute gas costs
- Road trip gas cost: enter the total miles from your map app. At $3.25 a gallon in a 30 mpg car, a 1,000-mile road trip costs about $108.33.
- Round trip: choose Round trip and enter the one-way distance; the calculator doubles it.
- Monthly commute: one-way commute × 2 × working days. A 20-mile commute over 21 days is 840 miles, about $91.00 a month at 30 mpg.
- Splitting the cost: divide the trip fuel cost by the number of people sharing the ride.
Tips to cut fuel costs
- Check tyre pressure monthly; under-inflated tyres lower MPG.
- Steady highway speeds use less fuel than hard acceleration.
- Remove roof racks and extra weight when you are not using them.
Buying a car? Compare running costs in the car affordability calculator and see the loan with the car payment calculator.
Frequently asked questions
How do I calculate the gas cost of a trip?
Divide the distance by your car’s miles per gallon to get the gallons used, then multiply by the price per gallon. A 300-mile trip at 30 mpg uses 10 gallons; at $3.25 a gallon that costs $32.50.
What MPG should I use?
Use the combined EPA rating for your car from fueleconomy.gov, or the average your dashboard shows. Highway trips usually beat the combined figure; city driving and heavy loads do worse.
How much does gas cost per mile?
Price per gallon divided by MPG. At $3.25 a gallon, a 25 mpg car costs $0.130 a mile and a 40 mpg car $0.081 a mile.
How do I work out gas cost for a road trip?
Add up the miles for the whole route, then use the gas cost calculator: miles ÷ MPG × price per gallon. Add 5% to 10% for city driving, detours and air conditioning.
How much do I spend on gas a month?
Driving 12,000 miles a year in a 25 mpg car at $3.25 a gallon costs about $130.00 a month.