US Gas Cost Calculator

Gas cost per mile = price per gallon / miles per gallon. At $3.50/gallon and 28 MPG, that's $0.125/mile. Drive 1,000 miles, fuel costs $125. A 250-mile road trip in a 28 MPG car at $3.50/gallon: $31.25 in fuel. Same trip in a 15 MPG truck: $58.33. The MPG difference dominates fuel cost - 50% better MPG saves about 33% on fuel.

US gas prices vary widely by region. California averages around $4.50-5.00/gallon, Texas $2.80-3.30, the national average around $3.20-3.60 in early 2025. Diesel is typically $0.30-0.60/gallon higher than regular gasoline. Premium fuel (91-93 octane) is $0.40-0.80 above regular - only worth using if your owner's manual requires it.

EPA-listed MPG ratings are based on standardised tests. Real-world MPG depends on driving style, terrain, weather, and load. Highway MPG usually beats city MPG by 30-50% in most vehicles. Aggressive acceleration drops MPG by 15-30%. Cold winter driving cuts MPG by 10-20% (more time in cold-start mode, denser air resistance).

Track real MPG by dividing miles since last fillup by gallons added. After 3-4 fillups, you have a reliable personal average. Apps like Fuelly (free) automate this. If your real MPG is consistently 20%+ below EPA estimates, check tyre pressure (under-inflated = significant MPG loss), air filter, and driving habits before assuming the engine has issues.

Electric vehicles cost roughly $0.04-0.08/mile depending on home electricity rates, vs $0.10-0.20/mile for gas cars. A 12,000 mile/year driver typically spends $1,400-2,500 on gas vs $500-1,000 on home charging. Public DC fast charging is more expensive ($0.30-0.50/kWh) and erodes the savings, but most EV charging is at home overnight at much cheaper rates.

Total cost of ownership for EVs includes higher upfront cost (often $7-15k more than equivalent gas car after tax credits), lower maintenance (no oil changes, fewer brake pads due to regen braking), and battery longevity (most modern EVs warranted 8-10 years). The [US EV Tax Credit Checker](/us-ev-tax-credit-checker) handles federal incentives.

Top three real-world MPG improvements: (1) Drive 65-70 mph on highways instead of 75-80 mph, gains 10-15% MPG. (2) Keep tyres properly inflated, gains 3-5% MPG. (3) Reduce unnecessary cargo weight - every 100 lbs of removed weight gains 1-2% MPG. Using AC sparingly helps in city driving but matters less at highway speeds.

Loyalty programs (Costco, Sam's Club, grocery store gas points) can save 5-15 cents/gallon. Apps like GasBuddy show real-time prices in your area. Filling up weekday mornings often beats peak weekend evenings. None of these dwarf MPG/driving habits but they add up - $0.10/gallon saved on 800 gallons/year is $80.