How To Calculate Fuel Cost for a Trip
Calculating fuel cost for any trip requires three pieces of information: the total distance of your trip, your vehicle's fuel efficiency in miles per gallon (MPG), and the current price of gas per gallon.
Formula:
Example — 300 mile trip in a vehicle that gets 30 MPG at $3.50 per gallon:
Fuel Cost = (300 ÷ 30) × $3.50 = 10 gallons × $3.50 = $35.00
Metric formula (liters per 100km):
Fuel Cost = (Distance in km ÷ 100) × Fuel Consumption (L/100km) × Price Per Liter
Our calculator handles both imperial and metric inputs automatically. You can find your vehicle's official MPG or L/100km rating on the EPA fuel economy label, your owner's manual, or at fueleconomy.gov.
Miles Per Gallon — What Is a Good MPG?
MPG measures how far your vehicle travels on one gallon of fuel. A higher MPG means better fuel efficiency and lower fuel costs.
Average MPG by vehicle type (2026):
| Vehicle Type | City MPG | Highway MPG | Combined MPG |
|---|---|---|---|
| Subcompact car | 28 – 35 | 36 – 45 | 30 – 38 |
| Midsize sedan | 24 – 32 | 32 – 42 | 27 – 35 |
| Full size sedan | 20 – 28 | 28 – 38 | 23 – 32 |
| Compact SUV | 22 – 30 | 28 – 36 | 24 – 32 |
| Midsize SUV | 18 – 25 | 24 – 32 | 20 – 27 |
| Full size SUV | 14 – 20 | 18 – 26 | 16 – 22 |
| Pickup truck | 14 – 22 | 18 – 28 | 16 – 24 |
| Hybrid sedan | 42 – 54 | 38 – 50 | 40 – 52 |
| Plug-in hybrid | 35 – 55 | 32 – 50 | 38 – 52 |
What counts as good MPG:
- Above 30 MPG combined — good fuel economy for a non-hybrid
- Above 40 MPG combined — excellent, typically hybrid territory
- Below 20 MPG combined — poor fuel economy, high operating cost
Real-world MPG is typically 10 to 20 percent lower than EPA estimates due to driving habits, traffic, weather, tire pressure, and vehicle load.
Road Trip Fuel Cost Calculator
Planning a road trip requires accurate fuel cost estimates so you can budget effectively. Fuel is typically the second largest road trip expense after lodging.
Fuel cost estimates for popular US road trips (gas at $3.50/gallon):
| Route | Distance | 25 MPG Vehicle | 35 MPG Vehicle | 45 MPG Hybrid |
|---|---|---|---|---|
| New York to Miami | 1,280 miles | $179 | $128 | $99 |
| Los Angeles to San Francisco | 380 miles | $53 | $38 | $30 |
| Chicago to Denver | 1,000 miles | $140 | $100 | $78 |
| Dallas to New Orleans | 500 miles | $70 | $50 | $39 |
| Seattle to Las Vegas | 1,100 miles | $154 | $110 | $86 |
| New York to Chicago | 790 miles | $111 | $79 | $61 |
- Maintain a steady highway speed — fuel efficiency drops significantly above 65 mph
- Keep tires properly inflated — under-inflated tires can reduce MPG by 2 to 3 percent
- Avoid excessive idling — a modern engine uses less fuel by restarting than idling for more than 30 seconds
- Use cruise control on highways to maintain consistent speed
- Plan routes to avoid stop-and-go traffic where possible
- Pack light — every 100 pounds of extra weight reduces fuel economy by approximately 1 percent
Cost Per Mile — How Much Does It Really Cost To Drive?
Cost per mile is one of the most useful metrics for understanding your true driving costs. It goes beyond just fuel to capture the full operating cost of your vehicle.
Fuel cost per mile by MPG and gas price:
| MPG | $3.00/gallon | $3.50/gallon | $4.00/gallon | $4.50/gallon |
|---|---|---|---|---|
| 20 MPG | $0.150 | $0.175 | $0.200 | $0.225 |
| 25 MPG | $0.120 | $0.140 | $0.160 | $0.180 |
| 30 MPG | $0.100 | $0.117 | $0.133 | $0.150 |
| 35 MPG | $0.086 | $0.100 | $0.114 | $0.129 |
| 40 MPG | $0.075 | $0.088 | $0.100 | $0.113 |
| 50 MPG | $0.060 | $0.070 | $0.080 | $0.090 |
Annual fuel cost estimate by daily commute distance:
| Daily Commute | 25 MPG at $3.50 | 35 MPG at $3.50 | 45 MPG at $3.50 |
|---|---|---|---|
| 20 miles/day | $1,022 | $730 | $568 |
| 30 miles/day | $1,533 | $1,095 | $852 |
| 40 miles/day | $2,044 | $1,460 | $1,136 |
| 50 miles/day | $2,555 | $1,825 | $1,420 |
These estimates assume 250 working days per year. The difference between a 25 MPG and 45 MPG vehicle adds up to over $1,000 per year for a typical commuter.
Electric vs Gas — Fuel Cost Comparison
Electric vehicles (EVs) are significantly cheaper to fuel than gasoline vehicles. Understanding the cost difference helps you calculate long-term savings when considering an EV purchase.
Key comparison metrics (2026 averages):
| Metric | Gasoline Vehicle | Electric Vehicle |
|---|---|---|
| Fuel cost per mile | $0.10 – $0.18 | $0.03 – $0.05 |
| Annual fuel cost (15,000 miles) | $1,500 – $2,700 | $450 – $750 |
| Annual savings with EV | — | $1,000 – $2,000+ |
| Home charging cost (per kWh) | — | $0.13 – $0.17 |
| Public fast charging cost | — | $0.25 – $0.45/kWh |
| Fuel equivalent MPG (MPGe) | 25 – 35 MPG | 90 – 140 MPGe |
Cost to drive 100 miles:
- Average gas car at 30 MPG and $3.50/gallon: $11.67
- Average EV at 3.5 miles/kWh and $0.15/kWh: $4.29
EVs cost roughly 60 to 70 percent less per mile to fuel than gasoline vehicles at current electricity and gas prices. The savings are most significant for high-mileage drivers and those who charge primarily at home where electricity rates are lower.
Frequently Asked Questions
How much gas will I need for a 500 mile trip?
The amount of gas you need depends on your vehicle's fuel efficiency. At 25 MPG you will need 20 gallons. At 30 MPG you will need approximately 16.7 gallons. At 35 MPG you will need approximately 14.3 gallons. At $3.50 per gallon, that translates to $70, $58, and $50 respectively. Use our calculator above with your specific MPG for an exact figure.
How do I calculate fuel cost for a road trip?
Divide your total trip distance by your vehicle's MPG to get the number of gallons needed. Then multiply by the current gas price per gallon. For example, a 600 mile trip in a vehicle that gets 28 MPG requires approximately 21.4 gallons. At $3.50 per gallon, total fuel cost is approximately $75. Our calculator does this math instantly with your exact numbers.
How much does it cost to drive per mile?
Fuel cost per mile equals the gas price divided by your MPG. At $3.50 per gallon and 30 MPG, fuel costs approximately $0.117 per mile. At 25 MPG the cost rises to $0.14 per mile. Over 15,000 miles per year the difference between 25 MPG and 35 MPG at $3.50 per gallon is approximately $600 annually.
How can I improve my gas mileage?
The most impactful ways to improve real-world MPG are maintaining proper tire pressure, avoiding rapid acceleration and hard braking, reducing highway speed, minimizing unnecessary idling, removing excess weight from the vehicle, and keeping up with regular maintenance including air filter and spark plug replacement. Combining short trips reduces cold-start fuel consumption, which is significantly higher than warm-engine driving.
How much gas does an SUV use per mile?
A midsize SUV averaging 24 MPG combined uses approximately 0.042 gallons per mile. At $3.50 per gallon, that equals approximately $0.146 per mile or $2,190 per year at 15,000 miles. A full size SUV averaging 18 MPG uses approximately 0.056 gallons per mile, costing around $0.194 per mile or $2,917 per year at 15,000 miles.
What is the fuel cost comparison between electric and gas cars?
At current average US electricity rates of approximately $0.15 per kWh and gas prices around $3.50 per gallon, an electric vehicle typically costs $0.03 to $0.05 per mile to fuel compared to $0.10 to $0.18 per mile for a gasoline vehicle. For a driver covering 15,000 miles per year, this represents annual fuel savings of approximately $1,000 to $2,000 in favor of the electric vehicle.
How do I calculate liters per 100 kilometers?
Divide the number of liters used by the distance traveled in kilometers, then multiply by 100. For example, if your vehicle uses 45 liters to travel 500 kilometers, your fuel consumption is (45 ÷ 500) × 100 = 9.0 L/100km. Lower numbers indicate better fuel efficiency. To convert L/100km to MPG, divide 235.21 by the L/100km figure.
What is my average monthly gas cost for commuting?
Multiply your daily round trip commute distance by the number of working days per month (typically 21 to 22), divide by your MPG, and multiply by the gas price. For a 40 mile daily round trip at 28 MPG and $3.50 per gallon with 22 working days: (40 × 22) ÷ 28 × $3.50 = 880 ÷ 28 × $3.50 = approximately $110 per month in fuel costs.
Last updated: 2026 | Estimates are illustrative. Actual consumption will vary depending on road conditions and driving style.