Gas Cost Calculator
Formula
Cost = (Distance ÷ MPG) × Gas Price
Divide your trip distance by your car's fuel efficiency (MPG) to get gallons needed, then multiply by the gas price per gallon.
How to use
- Enter your trip length in the Distance (miles) field.
- Enter your car's Fuel Efficiency in miles per gallon.
- Enter the Gas Price per gallon, then read the Trip Cost.
Example
For a 300-mile trip at 28 MPG with gas at $3.50/gal: 300 ÷ 28 = 10.7 gallons needed, then 10.7 × $3.50 ≈ $37.50 in fuel.
Frequently Asked Questions
What is average MPG?
The average US car gets about 25-30 MPG. SUVs average 20-25 MPG. Hybrids get 40-60 MPG.
How do I find my car's MPG?
Check your owner's manual or fueleconomy.gov. You can also calculate it: miles driven ÷ gallons filled.
How do I calculate the gas cost of my daily commute?
Add up your round-trip mileage, multiply by the number of days you drive, and run that total distance through the same formula: divide by your car's MPG and multiply by the gas price. For example, a 30-mile round trip driven 20 days a month is 600 miles; at 28 MPG and $3.50/gal that's about $75 a month. Tracking this helps you compare driving costs against transit or carpooling.
Does highway or city driving change the gas cost?
Yes, because your real-world MPG varies with driving conditions. Most cars get better mileage on the highway at steady speeds and worse in stop-and-go city traffic, so a single MPG number is an estimate. For the most accurate trip cost, use your car's highway MPG for long road trips and its city MPG for around-town driving.