⛽Gas Mileage Calculator
Work out your MPG and cost per mile — or how much gas a road trip will cost.
Your driving
Your fuel economy
30.0 MPG
30.0 MPG · $0.117 per mile · $35.00 for this fill-up
MPG
30.0
cost per mile
$0.117
fuel cost
$35.00
fuel (gal)
10.0
For the most accurate MPG, fill the tank completely, reset your trip meter, and divide miles by gallons at the next full fill-up.
How it works
- MPG = miles driven ÷ gallons used
- Trip fuel = trip miles ÷ MPG, and cost = gallons × price per gallon
- Cost per mile = fuel cost ÷ miles
Worked example
You drove 300 miles on 10 gallons at $3.50/gal:
- 300 ÷ 10 = 30 MPG
- 10 × $3.50 = $35 → $0.117 per mile
Questions people ask
Fill up, reset your trip meter, drive, then fill up again. Divide the miles driven by the gallons it took to refill.
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Last updated October 8, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.