Fuel Savings Calculator

Upgrading from 20 MPG to 35 MPG on 15,000 miles/year at $3.50/gal saves about $1,125/year. The savings are largest when going from poor to average MPG — going from 15 to 25 MPG saves more than 30 to 40 MPG.

If a hybrid costs $3,000 more and saves $1,000/year in fuel, it pays for itself in 3 years. With average ownership of 7-8 years, you'd save $4,000-5,000 net. Higher gas prices make the payback period even shorter.

Due to the inverse relationship: going from 10 to 20 MPG saves 50 gallons per 1,000 miles, but going from 30 to 40 MPG saves only 8.3 gallons. The biggest savings come from improving the least efficient vehicles.