How much will gas cost for my trip, and what is each person's share?
Use your car's real-world MPG for best accuracy.
How this is calculated
Formula: Cost = miles ÷ MPG × price per gallon; share = cost ÷ people.
Assumptions: Steady MPG. Heavy loads, roof boxes, mountains and high speeds can lower MPG 10–20%. Tolls and parking are not included.
Frequently asked questions
Should the driver pay a share?
Groups differ. Some count the driver so everyone pays equally; others leave the driver out to cover wear and tear.
What about wear and tear?
The IRS 2025 business mileage rate was 70¢ per mile, which includes gas, maintenance and depreciation, if you want a fuller cost.
How do I find my real MPG?
Fill up, reset the trip meter, drive, refill, and divide miles by gallons added.
Does AC use much gas?
A few percent at highway speeds; usually less than opening windows at high speed.