Fuel Cost Calculator

Step 1: Enter the total distance of your trip in miles.

Step 2: Enter your vehicle's fuel efficiency in miles per gallon (MPG). Check your car's window sticker, owner's manual, or fueleconomy.gov for the EPA rating. Highway driving gets better MPG than city driving.

Step 3: Enter the current fuel price per gallon. Check GasBuddy or local gas station signs for current prices.

Step 4: Click Calculate. The result shows the estimated fuel cost. The breakdown includes the total gallons needed and the per-mile cost.

Fuel cost depends on three factors: distance, fuel efficiency, and fuel price. Doubling any one of these doubles the cost (or halves it, in the case of efficiency).

MPG (Miles Per Gallon) measures how far your car travels on one gallon of fuel. The average US car gets about 25 MPG. Compact cars get 30-40 MPG, SUVs get 18-25 MPG, trucks get 15-22 MPG, and hybrids get 45-55 MPG. Electric vehicles use MPGe (miles per gallon equivalent) for comparison.

City vs highway MPG: Cars are more fuel-efficient at steady highway speeds (typically 45-65 mph) than in stop-and-go city traffic. The EPA rates vehicles separately for city and highway. Most long trips use the highway figure. City driving can be 20-30% less efficient.

Fuel prices in the US fluctuate significantly by region and time of year. As of early 2026, regular gasoline averages $3.00-4.00 per gallon nationally, with California and Hawaii typically $1-2 higher. Diesel is generally $0.50-1.00 more per gallon than regular gasoline.

Real-world vs EPA ratings: Your actual MPG may be 10-20% lower than the EPA estimate due to driving habits, tire pressure, air conditioning, cargo weight, and road conditions. Aggressive acceleration and high-speed driving significantly reduce fuel economy.

Gallons Needed = Distance ÷ MPG

Total Cost = Gallons × Price per Gallon

Cost per Mile = Price per Gallon ÷ MPG

Example: 450-mile road trip, 28 MPG car, $3.50/gallon.
- Gallons = 450 ÷ 28 = 16.07 gallons
- Cost = 16.07 × $3.50 = $56.25
- Per mile = $3.50 ÷ 28 = $0.125/mile

Round trip: Multiply by 2.
- Round trip cost = $56.25 × 2 = $112.50

Example 1: Daily Commute Cost
30-mile round trip, 25 MPG, gas at $3.50. Enter 30, 25, 3.50. Daily cost: $4.20. Over 22 work days per month: ~$92.40. Over a year: ~$1,108.

Example 2: Road Trip Budget
Family road trip: 800 miles each way, SUV gets 22 MPG, gas at $3.75. Enter 800, 22, 3.75. One way: $136.36. Round trip: ~$273.

Example 3: Comparing Vehicles
Which costs less for a 500-mile trip? Car A: 20 MPG. Car B: 35 MPG. Gas at $3.50.
- Car A: 500/20 × 3.50 = $87.50
- Car B: 500/35 × 3.50 = $50.00
- Car B saves $37.50 per trip.

Use highway MPG for road trips. Highway efficiency is typically 20-30% better than city. For mixed driving, use the combined EPA rating.

Keep tires properly inflated. Under-inflated tires increase rolling resistance and fuel consumption by 2-3%. Check tire pressure monthly.

Drive at moderate speeds. Fuel economy drops significantly above 50 mph. Every 5 mph over 50 costs roughly an extra $0.15-0.30 per gallon in fuel.

Calculate cost per mile for budgeting. Divide your gas price by your MPG. At $3.50/gal and 30 MPG, you spend about $0.12 per mile on fuel alone.

Compare fuel costs when car shopping. A car that gets 35 MPG vs 25 MPG saves about $750/year at 15,000 miles and $3.50/gal.