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Gas Cost Calculator

Estimate the fuel cost of a road trip or your entire year of driving — and compare two vehicles to see how much better MPG saves you.

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Gas Cost by the Numbers

Fuel is one of the largest ongoing costs of vehicle ownership. Even a modest improvement in MPG can translate to hundreds of dollars in annual savings.

How Much Does MPG Really Matter?

The relationship between MPG and fuel cost is non-linear. Improving from 10 to 20 MPG saves far more fuel than improving from 40 to 50 MPG — even though both are 10 MPG gains.

MPG Annual Cost (12,000 mi @ $3.50/gal)
15 MPG $2,800
20 MPG $2,100
25 MPG $1,680
30 MPG $1,400
35 MPG $1,200
40 MPG $1,050
50 MPG $840

Tips to Improve Fuel Economy

  • Keep tires properly inflated — Under-inflated tires can reduce MPG by 0.2–0.3% per PSI below optimal
  • Avoid jackrabbit starts — Smooth acceleration and braking is the single most effective habit change
  • Reduce highway speed — Fuel economy drops significantly above 55–60 mph due to aerodynamic drag
  • Remove excess weight — Every 100 lbs reduces MPG by about 1%
  • Use cruise control on highways to maintain steady speed

Average MPG by Vehicle Type (2025)

Vehicle Type Typical Combined MPG
Large truck / SUV 16–22
Midsize sedan 28–35
Compact / subcompact 32–40
Hybrid sedan 45–55
Plug-in hybrid 50–80 MPGe

Frequently Asked Questions

How do I find the official MPG for my vehicle?
Check fueleconomy.gov (the official U.S. government source), which lists EPA fuel economy ratings for all vehicles sold in the US since 1984. Real-world MPG is typically 10–20% lower than EPA estimates.

What is a good gas cost per mile?
At $3.50/gallon, a vehicle getting 30 MPG costs about $0.117 per mile in fuel. The IRS standard mileage rate (which includes fuel, maintenance, and depreciation) is about $0.67/mile in 2025.

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