Introduction
The Gas Mileage Calculator helps you figure out how many miles your car gets per gallon of gas. Just enter how far you drove and how much gas you used, and the calculator does the math for you. Knowing your gas mileage is important because it tells you how well your car uses fuel. A higher number means your car is more efficient and you spend less money at the pump. Whether you drive a truck, sedan, or SUV, tracking your gas mileage can help you save money and spot problems with your car early. If your mileage drops, it could mean your engine needs a tune-up or your tires need air. Use this simple tool to stay on top of your fuel costs and keep your car running its best.
How to Use Our Gas Mileage Calculator
Enter your driving distance and fuel details to find out your car's gas mileage, fuel cost, and efficiency rating. This tool has two modes: a Quick Calculator for simple mileage checks and a Trip Planner for estimating fuel costs on longer drives.
Quick Calculator
Unit System: Pick the unit system that works for you. Choose US (miles per gallon), Metric (kilometers per liter), or UK (miles per imperial gallon). The calculator will update all labels and default values to match your choice.
Distance Mode: Use the toggle switch to choose how you want to enter your distance. You can either type in your previous and current odometer readings, or enter the total distance you drove directly.
Previous Odometer Reading: If using odometer mode, type the number shown on your odometer before your trip started. This must be a positive number.
Current Odometer Reading: If using odometer mode, type the number shown on your odometer at the end of your trip. This number must be higher than your previous reading.
Distance Driven: If you toggled on direct distance mode, type the total number of miles or kilometers you drove.
Fuel Added to Tank: Enter the amount of fuel you put into your car in gallons, liters, or imperial gallons, depending on your chosen unit system.
Fuel Price (optional): Type the price you paid per gallon or liter of fuel. Pick your currency from the dropdown menu. If you fill this in, the calculator will show your total fuel cost and cost per mile or kilometer.
Click Calculate Mileage to see your results. You will get your fuel efficiency (like MPG or km/L), a color-coded rating from Excellent to Poor, the total distance driven, cost per mile or kilometer, and your total fuel cost. A gauge at the top gives you a quick visual of how your car is doing.
Trip Planner
Unit System: Just like the Quick Calculator, pick US, Metric, or UK units for your trip planning.
Route Stops: Enter your starting point and destination. You can also click Add Stop to include extra stops along your route, up to 10 total. Remove any extra stop by clicking the X button on its card.
Segment Distances: For each leg of your trip (like A to B, B to C), type in the driving distance. This lets you plan multi-stop routes with different distances between each stop.
Fuel Efficiency: Enter your car's fuel efficiency in MPG, km/L, or miles per imperial gallon. You can find this number in your car's owner manual or from a previous calculation using the Quick Calculator.
Fuel Price: Type the price per gallon or liter you expect to pay for fuel on your trip. Choose your currency from the dropdown.
Tank Size (optional): Enter the size of your car's fuel tank. If you provide this, the calculator will tell you how many full tank fills you will need for the entire trip.
Click Calculate Trip Cost to see your trip summary. You will get the total distance, total fuel needed, total fuel cost, cost per mile or kilometer, and the number of tank fills required. A segment breakdown table and chart show the distance, fuel, and cost for each leg of your trip.
What Is Gas Mileage?
Gas mileage tells you how far your car can travel on a set amount of fuel. In the United States, it is measured in miles per gallon (MPG). A higher MPG number means your car uses less fuel to go the same distance, which saves you money at the pump. In other countries, fuel efficiency is measured in kilometers per liter (km/L) or liters per 100 kilometers (L/100km).
How Is Gas Mileage Calculated?
The basic formula is simple: divide the distance you drove by the amount of fuel you used. For example, if you drove 360 miles and used 15 gallons of gas, your gas mileage is 360 ÷ 15 = 24 MPG. You can find the distance by subtracting your previous odometer reading from your current one, or by entering the distance directly if you already know it.
What Is Good Gas Mileage?
Gas mileage ratings vary a lot depending on the type of vehicle you drive:
- Excellent (40+ MPG): Hybrids and small, fuel-efficient cars often reach this level.
- Good (30–39 MPG): Many modern sedans and compact cars fall in this range.
- Average (22–29 MPG): This is typical for midsize cars and some crossover SUVs.
- Below Average (15–21 MPG): Larger SUVs and older vehicles often land here.
- Poor (below 15 MPG): Heavy-duty trucks and high-performance sports cars may get this kind of mileage.
Factors That Affect Your Gas Mileage
Several things can make your car use more or less fuel:
- Driving habits: Hard acceleration, speeding, and frequent braking all lower your MPG.
- Tire pressure: Underinflated tires create more resistance, which forces the engine to work harder. Use a Tire Size Calculator to make sure you have the right tires for your vehicle.
- Vehicle weight: Carrying heavy loads or towing a trailer reduces fuel efficiency.
- Road conditions: Stop-and-go city driving uses more gas than steady highway cruising.
- Weather: Cold temperatures, strong winds, and using the air conditioner can all hurt your mileage.
- Engine maintenance: Dirty air filters, old spark plugs, and skipped oil changes make your engine less efficient.
How to Improve Your Gas Mileage
You can take a few easy steps to get more miles out of every gallon:
- Drive at steady speeds and avoid rapid acceleration.
- Keep your tires inflated to the recommended pressure listed on the sticker inside your driver's door.
- Remove extra weight from your trunk or cargo area.
- Keep up with regular maintenance like oil changes and air filter replacements.
- Use cruise control on the highway when it is safe to do so.
- Plan your trips to combine errands and avoid unnecessary driving.
Why Tracking Gas Mileage Matters
Keeping an eye on your gas mileage over time helps you spot problems early. If your MPG suddenly drops, it could be a sign that something is wrong with your car, like a failing oxygen sensor, a clogged fuel injector, or a tire losing air. Tracking your fuel usage also makes it easier to budget for gas, especially on long road trips where fuel is one of the biggest expenses. If you're financing your vehicle, an Auto Loan Calculator can help you understand your total car ownership costs alongside fuel expenses. Knowing your cost per mile helps you compare driving costs to other options like flying or taking a train. You can also check your car's horsepower to better understand the relationship between engine power and fuel consumption, and use a Tint Calculator if you're considering window tinting to help reduce air conditioner use and improve efficiency in hot climates.