⛽ Trip & Fuel Details
Enter your trip distance, fuel efficiency and gas price
⛽ Your Fuel Cost Results
🚗 Compare Fuel Cost by Vehicle Type
How to Calculate Fuel Cost for a Trip
Calculating fuel cost is simple once you know three things — how far you are driving, how fuel efficient your vehicle is and what fuel costs at the pump. Our free fuel cost calculator handles all of this instantly and also shows you monthly fuel spending so you can budget accurately.
The Fuel Cost Formula
Fuel Cost = (Distance / Fuel Efficiency) × Fuel Price
For example: 100 miles / 30 MPG = 3.33 gallons × $3.50 per gallon = $11.67 total fuel cost for the trip.
Tips to Reduce Your Fuel Costs
- Maintain steady highway speeds — fuel efficiency drops significantly above 60 mph
- Keep tires properly inflated — under-inflated tires increase fuel consumption by up to 3%
- Remove unnecessary weight from your vehicle — every 100 lbs reduces efficiency by 1%
- Use cruise control on highways to maintain consistent speed
- Avoid aggressive acceleration and braking — smooth driving saves 10-40% fuel
- Plan routes to avoid traffic — idling burns fuel with zero distance covered
- Compare fuel prices using apps like GasBuddy before filling up
Average Fuel Efficiency by Vehicle Type
- Electric vehicles — equivalent 100+ MPGe
- Hybrid vehicles — 40-60 MPG
- Small cars — 30-40 MPG
- Midsize sedans — 25-35 MPG
- SUVs and crossovers — 20-30 MPG
- Pickup trucks — 15-25 MPG
- Large SUVs and vans — 12-20 MPG
Fuel Cost Calculator — Calculate Trip, Monthly and Annual Fuel Expenses
Fuel cost calculation tells you exactly how much a journey, commute or annual driving costs in petrol or diesel. Whether you are planning a road trip, comparing two vehicles' running costs or budgeting your monthly motoring expenses, understanding fuel economics helps you make better financial decisions. Our fuel cost calculator works with both MPG/miles and L/100km/kilometres systems for US, UK and international drivers.
The Fuel Cost Formula — How to Calculate Any Journey
Fuel Cost = (Distance ÷ Fuel Efficiency) × Fuel Price. In imperial units: (Miles ÷ MPG) × Price per gallon. In metric units: (Km × L/100km ÷ 100) × Price per litre. For a 400-mile road trip at 32 MPG with fuel at $3.60/gallon: (400 ÷ 32) × $3.60 = 12.5 gallons × $3.60 = $45.00. For a 600km trip at 7.5 L/100km at $1.75/litre: (600 × 7.5 ÷ 100) × $1.75 = 45 litres × $1.75 = $78.75. Our calculator handles both systems — just enter your numbers and get the cost instantly. Use our budget calculator to include fuel costs within your full monthly budget.
| Vehicle Type | Typical MPG | L/100km | Cost per 100 miles @ $3.50 |
|---|---|---|---|
| Small/Hybrid | 40–55 MPG | 4.3–5.9 | $6.36–$8.75 |
| Mid-size Sedan | 28–35 MPG | 6.7–8.4 | $10.00–$12.50 |
| SUV / Crossover | 22–28 MPG | 8.4–10.7 | $12.50–$15.91 |
| Truck / Large SUV | 15–22 MPG | 10.7–15.7 | $15.91–$23.33 |
Annual Fuel Cost — Comparing Vehicles
The fuel cost difference between vehicles compounds significantly over time. A driver covering 15,000 miles annually at $3.50/gallon: a 50 MPG hybrid costs $1,050/year in fuel; a 30 MPG sedan costs $1,750/year; a 20 MPG SUV costs $2,625/year. The hybrid saves $1,575 per year over the SUV — enough to offset a significant price premium in a few years. When comparing vehicle purchase decisions, always calculate the 5-year fuel cost difference alongside the purchase price and financing cost to understand the true total cost of ownership. Our fuel cost calculator lets you compare any two vehicles side by side by running separate calculations.
| MPG | Annual Cost (15k miles, $3.50) | 5-Year Cost | vs 30 MPG (5yr) |
|---|---|---|---|
| 50 MPG | $1,050 | $5,250 | Save $3,500 |
| 35 MPG | $1,500 | $7,500 | Save $1,250 |
| 30 MPG | $1,750 | $8,750 | Baseline |
| 20 MPG | $2,625 | $13,125 | +$4,375 more |
Electric Vehicle Running Costs — Comparing EV to Petrol
EVs use kWh per 100 miles instead of MPG. The EPA equivalent — MPGe (miles per gallon equivalent) — allows comparison. To calculate EV running cost: Cost = (Miles ÷ Miles per kWh) × Electricity price per kWh. A car getting 4 miles per kWh driven 15,000 miles at $0.14/kWh: (15,000 ÷ 4) × $0.14 = $525/year — roughly half the fuel cost of a 30 MPG petrol car at $3.50/gallon ($1,750/year). Home charging overnight at off-peak rates (often $0.08-$0.10/kWh) reduces EV running costs further. Public fast-charging rates ($0.30-$0.50/kWh) narrow the cost advantage significantly.
Road Trip Cost Planning
For multi-stop road trips, calculate fuel cost for each segment separately if fuel prices vary significantly along the route, then sum the totals. Major US highway corridors have average fuel prices available on GasBuddy or AAA's fuel gauge reports. For international trips, convert between measurement systems: 1 US gallon = 3.785 litres; 1 mile = 1.609 km. Budget approximately 10-15% more than the calculated fuel cost as a buffer for detours, price variations and efficiency reductions from highway speeds, air conditioning use and cargo weight. Add our savings calculator to your road trip planning to see how much you save by choosing a more fuel-efficient vehicle for the journey.
Fuel Economy Tips — Getting More Miles Per Gallon
Real-world fuel economy often differs from EPA estimates due to driving habits, conditions and maintenance. Speed significantly affects efficiency — most vehicles peak efficiency at 45-55 mph and lose efficiency rapidly above 65 mph (aerodynamic drag increases with the square of speed). Air conditioning typically reduces fuel economy by 5-25% in city driving. Cold weather reduces efficiency as engines take longer to reach optimal operating temperature and EV batteries lose capacity. Proper tire pressure (check monthly) can improve economy by 0.5-3%. Fresh air filters, proper oil viscosity and regular spark plug replacement each contribute modestly. The single biggest factor is driver behaviour — smooth, anticipatory driving with gradual acceleration and coasting to stops versus aggressive driving can improve real-world economy by 20-30%. Whether you are calculating the cost of a daily commute, comparing petrol vs diesel vs electric running costs, planning a road trip budget or evaluating whether a more fuel-efficient vehicle makes financial sense for your mileage, our fuel cost calculator gives you instant accurate answers. Enter your distance, fuel efficiency and current fuel price above to calculate your trip cost, cost per mile and annual fuel expense in one click.
Carpooling and Shared Commute Savings
Carpooling with just one other person halves your fuel cost immediately. A 30-mile round trip commute at 28 MPG and $3.60/gallon costs $231/month solo — shared with one colleague it drops to $115.50 each. With three colleagues: $57.75 each. Apps like Waze Carpool, Scoop and employer rideshare platforms connect commuters travelling the same route. Beyond fuel savings, carpooling reduces vehicle wear and tear, lowers parking costs in paid lots and qualifies many drivers for HOV lane access that reduces commute time. Even alternating driving weeks with a colleague — so each person drives every other week — cuts monthly fuel costs by 50% for commuting trips. When planning shared travel costs, our fuel cost calculator makes it simple to calculate each person's share: calculate total trip fuel cost, then divide by the number of passengers.