Updated on April 19th, 2026

Fuel Cost Calculator

Created By Jehan Wadia

Trip Details
— or enter distance manually —
Effective distance: 500 miles
Vehicle & Fuel Efficiency
Vehicle A
— or enter fuel efficiency manually —
Fuel Price
Time-Based Budget Projection

Fuel Cost Results

Total Fuel Cost

$60.00

Fuel Needed

20.00 gallons

Cost per Mile

$0.12

Environmental Impact

CO₂ Emissions

176.00 kg

Trees to Offset

8

Equivalent EV kWh

166.67 kWh

Time-Based Budget Projection
Period Trips Distance Fuel Used Cost

Introduction

The Fuel Cost Calculator helps you figure out how much money you will spend on gas for any trip. Just enter your trip distance, your car's fuel efficiency (miles per gallon), and the current price of gas. The calculator does the math for you and tells you the total fuel cost in seconds. Whether you are planning a road trip, budgeting for your daily commute, or comparing fuel costs between different cars, this tool makes it simple. Knowing your fuel costs ahead of time helps you plan better and save money at the pump.

How to Use Our Fuel Cost Calculator

Enter your trip distance, vehicle fuel efficiency, and fuel price to find out how much your trip will cost in gas, how much fuel you will need, and what your long-term fuel budget looks like.

Starting Location, Destination, and Additional Stop: Pick a starting city and a destination from the dropdown menus to auto-fill the trip distance. You can also add an optional extra stop along the way. If your cities are not listed, skip this and type the distance in manually.

Trip Distance: Enter the total one-way distance of your trip in miles or kilometers. This is the number the calculator uses to figure out how much fuel you will need.

Round Trip: Check this box if you are driving to your destination and back. It doubles the distance for you automatically.

Vehicle Make, Year, and Model: Select your car's make, year, and model from the dropdown lists. The calculator will fill in the fuel efficiency (miles per gallon) for that vehicle. If your car is not listed, skip this and enter the efficiency yourself.

Fuel Efficiency: Enter how many miles your car gets per gallon, or use another unit like liters per 100 km, km per liter, or liters per mile. A higher MPG number means your car uses less gas and your trip costs less. You can also use our Gas Mileage Calculator to determine your car's actual real-world fuel efficiency based on fill-up data.

Compare Two Vehicles: Turn this toggle on to add a second vehicle. This lets you see the fuel cost side by side for two different cars so you can find out which one saves you more money.

Fuel Price: Enter the current price you pay for gas per gallon or per liter. You can also click the "Use National Average" button to auto-fill the latest U.S. average gas price.

Currency: Choose your currency from the dropdown list. The calculator supports USD, EUR, GBP, JPY, INR, CAD, AUD, and BRL.

Trips per Week: Enter how many times you make this trip each week. This is used to project your fuel spending over time in the budget table and chart.

Projection Period (Weeks): Enter the number of weeks you want the calculator to project your fuel costs into the future. For example, enter 52 to see a full year of fuel spending broken down by week, month, quarter, and year.

Fuel Cost Calculator – Know What You'll Spend on Gas

Fuel is one of the biggest costs of owning and driving a car. Whether you're planning a road trip, figuring out your daily commute expenses, or setting a monthly budget, knowing how much you'll spend on gas helps you plan ahead and save money. This fuel cost calculator lets you quickly find out the total cost of fuel for any trip based on your distance, your car's fuel efficiency, and the current price of gas. If you're financing a vehicle, don't forget to factor in your monthly payment using an Auto Loan Calculator alongside your fuel expenses for a complete picture of car ownership costs.

How Fuel Costs Are Calculated

The basic math behind fuel cost is simple. You take the total distance you plan to drive, divide it by your car's miles per gallon (MPG), and then multiply by the price of gas. For example, if you're driving 500 miles in a car that gets 25 MPG with gas at $3.00 per gallon, you would need 20 gallons of fuel and spend $60.00. The formula looks like this:

Fuel Cost = (Distance ÷ MPG) × Price per Gallon

What Affects Your Fuel Efficiency

Your car's real-world fuel efficiency can differ from the number on the sticker. Several things change how much gas your car actually uses:

Comparing Two Vehicles

If you're thinking about buying a new car or choosing between two vehicles for a trip, comparing their fuel costs side by side can reveal big differences. A car that gets 35 MPG versus one that gets 20 MPG will save you hundreds of dollars over a year of regular driving. Even a small difference in MPG adds up fast, especially for people who commute long distances every day.

Understanding the Environmental Impact

Every gallon of gasoline burned produces about 8.9 kilograms of carbon dioxide (CO₂). That CO₂ goes into the atmosphere and contributes to climate change. This calculator shows you the CO₂ your trip creates, how many trees it would take to absorb that amount in a year, and how much electricity an electric vehicle would need to cover the same distance. One tree absorbs roughly 22 kg of CO₂ per year, so a single 500-mile trip in an average car creates enough CO₂ to keep about 8 trees busy for a whole year. If you're also curious about how your car's engine converts fuel into power, check out the Horsepower Calculator to explore the relationship between engine performance and energy output.

Tips to Lower Your Fuel Costs

By understanding what you spend on fuel and what drives those costs up or down, you can make smarter choices about how you drive, which car you buy, and how you budget your money. For a broader view of your overall financial health and how transportation costs fit into the big picture, try our Net Worth Calculator to track all of your expenses and assets in one place.


Frequently Asked Questions

What is a fuel cost calculator?

A fuel cost calculator is a tool that tells you how much money you will spend on gas for a trip. You enter your trip distance, your car's miles per gallon (MPG), and the price of gas. It then calculates the total fuel cost, how many gallons you need, and your cost per mile.

How do I find my car's MPG if I don't know it?

You can check your car's owner manual, look at the sticker on the driver's side door, or search your car's make and model on fueleconomy.gov. This calculator also has a built-in vehicle database. Just pick your car's make, year, and model, and it will fill in the MPG for you.

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

MPG stands for miles per gallon. It tells you how many miles your car can drive on one gallon of gas. L/100km stands for liters per 100 kilometers. It tells you how many liters of fuel your car uses to go 100 km. A higher MPG means better fuel economy, but a lower L/100km means better fuel economy. They measure the same thing in different ways.

Does the round trip option change my fuel cost?

Yes. When you check the round trip box, the calculator doubles your trip distance. This means it also doubles the fuel needed and the total cost, since you are driving to your destination and back home again.

How accurate is the national average gas price button?

The national average price shown is a simulated estimate and may not match the exact current price. Gas prices change daily and vary by state and city. For the most accurate result, enter the actual price you see at your local gas station.

Can I calculate fuel costs in kilometers and liters?

Yes. You can switch the distance unit to kilometers and the fuel price unit to per liter. You can also set fuel efficiency to L/100km or km/L. The calculator will convert everything and give you the correct fuel cost no matter which units you use.

How does the vehicle comparison feature work?

Turn on the "Compare two vehicles" toggle. Enter the fuel efficiency for Vehicle A and Vehicle B. The calculator will show the fuel cost for both cars side by side, along with how much money the cheaper car saves you on the same trip.

What does the CO2 emissions result mean?

Every gallon of gas burned releases about 8.9 kg of CO₂ into the air. The calculator multiplies the gallons of fuel your trip uses by this number to show how much carbon dioxide your drive produces. It also shows how many trees would be needed to absorb that CO₂ in one year.

What does the equivalent EV kWh result mean?

This shows how many kilowatt-hours of electricity an electric vehicle would need to cover the same distance. It uses an average of 0.3 kWh per mile. This helps you compare the energy use of a gas car versus an electric car.

How does the time-based budget projection work?

You enter how many trips you make per week and how many weeks to project. The calculator then multiplies your single-trip fuel cost by those numbers to show your total fuel spending per week, per month, per quarter, and per year. It also creates a chart so you can see costs add up over time.

Why is my real fuel cost different from the calculator result?

Real fuel costs can vary because of traffic, driving speed, weather, road conditions, tire pressure, and how much weight is in your car. The calculator uses the MPG number you enter, but your actual MPG may be higher or lower depending on these factors.

Can I use this calculator for diesel vehicles?

Yes. Enter your diesel vehicle's fuel efficiency and the current price of diesel fuel. The calculator works the same way for diesel as it does for regular gasoline. Just make sure the price you enter matches the type of fuel you use.

What if my city is not in the location dropdown?

If your starting city or destination is not listed, skip the location dropdowns and type your trip distance directly into the Trip Distance field. The location feature only covers select major U.S. cities with pre-loaded distances between them.

How do I calculate fuel cost for a daily commute?

Enter your one-way commute distance, check the round trip box, and set your car's MPG and gas price. Then set trips per week to 5 (for a typical work week) and the projection period to 52 weeks. The calculator will show your weekly, monthly, and yearly commute fuel costs.

Does driving speed really affect fuel cost?

Yes. Most cars get their best MPG at around 45 to 55 mph. Driving at 70 or 80 mph can lower your fuel efficiency by 10% to 20% or more. That means you burn more gas and spend more money on the same trip when you drive faster.


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