Enter trip distance, fuel efficiency, and price above
Results appear as you typeWhat Is a Fuel Cost Estimator?
A Fuel Cost Estimator helps you calculate the total cost of fuel for a trip based on distance, vehicle fuel efficiency, and local fuel prices. It’s an essential tool for budgeting road trips, evaluating daily commutes, comparing vehicle costs, and planning logistics for fleets or deliveries.
Understanding your fuel costs allows you to make smarter decisions — whether that means choosing a more efficient route, carpooling, upgrading to a fuel-efficient vehicle, or simply budgeting accurately for an upcoming journey.
Key insight: Even small improvements in fuel efficiency (e.g., from 25 MPG to 30 MPG) can save hundreds of dollars annually for regular drivers.
Fuel Cost Formula
For MPG, fuel needed = distance ÷ MPG. For L/100km, fuel needed = (distance × fuel economy) ÷ 100. For km/L, fuel needed = distance ÷ km/L.
How to Use This Calculator
- 1Enter the distance of your trip — switch between miles or kilometers as needed.
- 2Enter your vehicle’s fuel efficiency — choose MPG, L/100km, or km/L based on your preference.
- 3Enter the current fuel price per gallon or liter (changes automatically with your efficiency unit).
- 4Select your currency to see costs in your local denomination.
- 5Optional: Add your tank size to see how many fill-ups you’ll need.
- 6Results appear instantly — total cost, fuel needed, cost per mile/km, estimated CO₂ emissions, and money-saving tips.
Worked Example
Planning a 300-mile road trip in a car that gets 25 MPG. Fuel costs $3.50 per gallon.
Typical Fuel Efficiency by Vehicle Type
30–40 MPG · 5.9–7.8 L/100km
20–28 MPG · 8.4–11.8 L/100km
15–22 MPG · 10.7–15.7 L/100km
40–60 MPG · 3.9–5.9 L/100km
10–18 MPG · 13.1–23.5 L/100km
45–60 MPG · 3.9–5.2 L/100km
Frequently Asked Questions
MPG stands for Miles Per Gallon — the distance (in miles) your vehicle can travel on one gallon of fuel. Higher MPG means better fuel efficiency. To calculate MPG manually: divide the miles driven by the gallons of fuel used. For example, 300 miles ÷ 12 gallons = 25 MPG.
MPG (Miles Per Gallon) is used primarily in the US, UK, and a few other countries. Higher MPG = better efficiency. L/100km (Liters per 100 kilometers) is used in most other countries. Lower L/100km = better efficiency. For conversion: 235.2 ÷ MPG = L/100km, and 235.2 ÷ L/100km = MPG.
Common ways to improve fuel efficiency: maintain proper tire pressure (can improve MPG by up to 3%), remove excess weight, avoid aggressive acceleration/braking, use cruise control on highways, reduce idling, keep up with engine maintenance, and combine trips to reduce cold starts.
Idling typically consumes 0.2–0.5 gallons of fuel per hour for a standard car (more for larger engines). At $3.50/gallon, that’s $0.70–$1.75 per hour. For trucks, idling can consume 0.8–1.5 gallons per hour. Reducing idling by just 10 minutes per day can save $20–$50 per year.
For gasoline vehicles, each gallon burned produces approximately 19.6 pounds of CO₂. For diesel, it’s about 22.4 pounds per gallon. The calculator multiplies fuel needed (in gallons) by these factors. For metric users: each liter of gasoline produces about 2.3 kg of CO₂.
Simply enter the total round-trip distance. For example, if your destination is 150 miles away, the round trip is 300 miles. Enter 300 miles in the calculator to get the total fuel cost for going there and coming back.