How to calculate gas cost
A 350-mile trip in a car that gets 28 mpg uses 12.5 gallons. At $3.25 a gallon, that's about $40.63.
Ways to use less fuel
- Keep tires inflated to the pressure on the driver's door sticker.
- Drive at a steady speed; fuel economy usually drops at highway speeds above about 50 to 60 mph.
- Remove roof racks and extra weight when you don't need them.
Monthly commute cost
To estimate a month of commuting, multiply your one-way distance by 2 and by the number of workdays. A 22-mile commute over 21 workdays is 924 miles. At 28 mpg and $3.25 a gallon, that's about 33 gallons, or roughly $107 a month.
Fuel economy and cost per mile
| Fuel economy | Cost per mile at $3.25/gal | Cost per 100 miles |
|---|---|---|
| 15 mpg | $0.217 | $21.67 |
| 20 mpg | $0.163 | $16.25 |
| 25 mpg | $0.130 | $13.00 |
| 30 mpg | $0.108 | $10.83 |
| 35 mpg | $0.093 | $9.29 |
| 40 mpg | $0.081 | $8.12 |
| 50 mpg | $0.065 | $6.50 |
Frequently asked questions
Where do I find my car's MPG?
Check your dashboard's trip computer or the window sticker. For a quick estimate, use the combined MPG rating for your model.
How do I compare an EV?
Electric cars use kilowatt-hours instead of gallons. Multiply miles by the car's kWh per mile and by your electricity rate.
Is gas the only cost of driving?
No. Tires, maintenance, insurance, and depreciation add to the cost of every mile. Gas is usually the biggest cost that changes with each trip, which is why it's the number people split on road trips.