If you're a typical American, you drive roughly 12,500 miles per year. If your car gets 25 miles per gallon, that means you buy about 500 gallons of gas during the year. When gas was selling for $2.80 per gallon, you spent $1,400 on fuel for the twelve-month period. At $3.80 per gallon, you'll spend $1,900 for the same amount of gas, an additional $500 over the course of the year, or an extra $42 per month. However, you can save money on gas by using tools available to you through your PC, tablet , and smartphone.