How do I calculate the fuel cost for a road trip?

Divide your total trip distance by your vehicle's fuel efficiency (MPG), then multiply by the current fuel price. Formula: Cost = (Distance ÷ MPG) × Price per gallon. For example, a 500-mile trip in a car getting 30 MPG with gas at $3.50/gallon: (500 ÷ 30) × $3.50 = $58.33. For metric: Cost = (Distance × L/100km ÷ 100) × Price per liter.

What is the difference between MPG and L/100km?

MPG (miles per gallon) is used in the US and measures how far you can drive on one gallon of fuel — higher is better. L/100km (liters per 100 kilometers) is used in most other countries and measures how much fuel you use per 100 km — lower is better. To convert: L/100km = 235.215 ÷ MPG. For example, 30 MPG = 7.84 L/100km.

How do I find my car's actual fuel efficiency?

Fill your tank completely, reset your trip odometer, drive normally until you need fuel again, then fill up again. Divide the miles driven by the gallons used: MPG = Miles ÷ Gallons. For metric: L/100km = (Liters used ÷ km driven) × 100. Real-world efficiency is usually 10-20% lower than EPA ratings due to driving conditions.

How much does it cost to drive 1,000 miles?

At 30 MPG with gas at $3.50/gallon: (1,000 ÷ 30) × $3.50 = $116.67. At 25 MPG: $140.00. At 35 MPG: $100.00. At 50 MPG (hybrid): $70.00. Actual costs vary with driving conditions, speed, terrain, and local gas prices. Highway driving is typically more fuel-efficient than city driving.

How can I improve my car's fuel efficiency?

Key tips: maintain steady speeds using cruise control, keep tires properly inflated (improves MPG by up to 3%), avoid aggressive acceleration and braking, drive at 55-65 mph (optimal range), remove excess weight and roof racks, use the recommended motor oil grade, keep up with maintenance (air filters, spark plugs), and combine short trips. AC use at highway speeds is more efficient than open windows.

How do I split gas costs fairly among passengers?

Calculate the total trip fuel cost, then divide by the number of passengers (including the driver). For example, a $60 fuel cost split among 4 people = $15 each. Some prefer the driver pays less since they provide the car and insurance. For carpools, apps like Splitwise can track ongoing fuel cost sharing.

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Fuel Cost Calculator

To calculate trip fuel cost: divide distance by fuel efficiency (MPG), then multiply by fuel price. Formula: Cost = (Distance ÷ MPG) × Price per gallon. For metric: Cost = (Distance × L/100km ÷ 100) × Price per liter. A 300-mile trip at 30 MPG with $3.50/gal gas costs $35.00.

Calculate trip fuel costs, fuel needed, and fuel efficiency. Supports US (mpg, gallons) and metric (L/100km, liters) units. Compare vehicles, split costs among passengers, and plan road trip budgets.

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What do you want to calculate?

Calculate the total fuel cost for your trip

Units:

Distance (miles)

Round trip (doubles distance)

Fuel Efficiency (mpg)

Fuel Price ($/gallon)

Split Among Passengers

person

Compare two vehicles

Average Fuel Efficiency by Vehicle Type

Vehicle Type	MPG	L/100km	Annual Fuel Cost*
Compact Car	35	6.7	$1200.00
Sedan	30	7.8	$1400.00
SUV	25	9.4	$1680.00
Truck	20	11.8	$2100.00
Hybrid	50	4.7	$840.00
EV Equivalent	120	2	$350.00

*Based on 12,000 miles/year at $3.50/gallon

Tips to Save on Fuel Costs

🚗 Driving Habits

• Maintain steady speed — use cruise control
• Avoid aggressive acceleration and braking
• Drive at or below speed limit (55-65 mph is optimal)
• Combine short trips into one

🔧 Vehicle Maintenance

• Keep tires properly inflated (+3% efficiency)
• Replace air filters regularly
• Use recommended motor oil grade
• Remove excess weight from trunk

⛽ Fuel Purchasing

• Use gas price apps (GasBuddy, Waze)
• Fill up on weekdays (often cheaper)
• Use grocery store fuel rewards
• Use a fuel rewards credit card

📍 Route Planning

• Avoid rush hour traffic when possible
• Use navigation apps for shortest routes
• Consider highway vs city driving
• Carpool to split fuel costs

Fuel Cost Formulas

Trip Cost (US)

Cost = (Distance ÷ MPG) × Price per gallon

Trip Cost (Metric)

Cost = (Distance × L/100km ÷ 100) × Price per liter

Fuel Efficiency

MPG = Distance ÷ Gallons used

L/100km = (Liters used ÷ Distance) × 100

MPG ↔ L/100km Conversion

L/100km = 235.215 ÷ MPG

MPG = 235.215 ÷ L/100km

How to Use

Enter your value in the input field
Click the Calculate/Convert button
Copy the result to your clipboard

Frequently Asked Questions

How do I calculate the fuel cost for a road trip?: Divide your total trip distance by your vehicle's fuel efficiency (MPG), then multiply by the current fuel price. Formula: Cost = (Distance ÷ MPG) × Price per gallon. For example, a 500-mile trip in a car getting 30 MPG with gas at $3.50/gallon: (500 ÷ 30) × $3.50 = $58.33. For metric: Cost = (Distance × L/100km ÷ 100) × Price per liter.
What is the difference between MPG and L/100km?: MPG (miles per gallon) is used in the US and measures how far you can drive on one gallon of fuel — higher is better. L/100km (liters per 100 kilometers) is used in most other countries and measures how much fuel you use per 100 km — lower is better. To convert: L/100km = 235.215 ÷ MPG. For example, 30 MPG = 7.84 L/100km.
How do I find my car's actual fuel efficiency?: Fill your tank completely, reset your trip odometer, drive normally until you need fuel again, then fill up again. Divide the miles driven by the gallons used: MPG = Miles ÷ Gallons. For metric: L/100km = (Liters used ÷ km driven) × 100. Real-world efficiency is usually 10-20% lower than EPA ratings due to driving conditions.
How much does it cost to drive 1,000 miles?: At 30 MPG with gas at $3.50/gallon: (1,000 ÷ 30) × $3.50 = $116.67. At 25 MPG: $140.00. At 35 MPG: $100.00. At 50 MPG (hybrid): $70.00. Actual costs vary with driving conditions, speed, terrain, and local gas prices. Highway driving is typically more fuel-efficient than city driving.
How can I improve my car's fuel efficiency?: Key tips: maintain steady speeds using cruise control, keep tires properly inflated (improves MPG by up to 3%), avoid aggressive acceleration and braking, drive at 55-65 mph (optimal range), remove excess weight and roof racks, use the recommended motor oil grade, keep up with maintenance (air filters, spark plugs), and combine short trips. AC use at highway speeds is more efficient than open windows.
How do I split gas costs fairly among passengers?: Calculate the total trip fuel cost, then divide by the number of passengers (including the driver). For example, a $60 fuel cost split among 4 people = $15 each. Some prefer the driver pays less since they provide the car and insurance. For carpools, apps like Splitwise can track ongoing fuel cost sharing.