Quick MPG Calculator
Enter your trip distance and fuel used to calculate miles per gallon (MPG). You can also add fuel price to estimate total trip fuel cost and cost per mile.
What is miles per gallon (MPG)?
Miles per gallon is a fuel economy measurement that tells you how many miles your car can travel using one gallon of fuel. A higher MPG number means your vehicle is more fuel-efficient. For everyday drivers, MPG helps answer one practical question: how far can I go for what I pay at the pump?
If you track your MPG regularly, you can spot changes in performance, compare vehicles, and reduce fuel expenses over time.
MPG formula
The formula is straightforward:
MPG = Miles Driven ÷ Gallons Used
Example:
- Miles driven: 300
- Gallons used: 10
- MPG: 300 ÷ 10 = 30 MPG
This calculator also estimates:
- L/100 km (a common international fuel economy metric)
- Total fuel cost (if fuel price is entered)
- Cost per mile
- Estimated CO₂ emissions based on gasoline consumption
How to use this miles to the gallon calculator
Step 1: Enter miles driven
Use your odometer or trip meter reading from the start and end of your trip (or between fill-ups).
Step 2: Enter gallons used
Use the amount shown on your fuel receipt or pump display.
Step 3: (Optional) Enter fuel price
If you want trip cost and cost-per-mile estimates, add your price per gallon.
Step 4: Click calculate
You’ll get your MPG instantly, along with extra useful driving cost insights.
What is considered good MPG?
“Good MPG” depends on vehicle type, engine size, and driving conditions. As a rough guide:
- Small gasoline cars: 30–40+ MPG
- Midsize sedans/SUVs: 22–32 MPG
- Trucks and large SUVs: 15–25 MPG
- Hybrids: 40–60+ MPG
Instead of comparing yourself to every vehicle on the road, compare your own MPG across time and routes. That gives you the most useful benchmark.
Why your MPG changes
If your fuel economy seems inconsistent, that’s normal. MPG fluctuates due to multiple factors:
- City traffic vs highway driving
- Speed (higher speed usually lowers MPG)
- Aggressive acceleration and braking
- Tire pressure and wheel alignment
- Vehicle load (passengers, cargo, towing)
- Weather and temperature
- Engine condition and maintenance schedule
Tips to improve fuel economy
Drive smoothly
Avoid hard starts and rapid braking. Gradual acceleration can noticeably improve mileage.
Watch your speed
Many vehicles lose efficiency above 60 mph. Slowing down slightly can save fuel on long trips.
Maintain your car
Regular oil changes, clean air filters, and properly inflated tires all help your vehicle operate efficiently.
Reduce extra weight
Unnecessary items in your trunk or roof rack increase drag and fuel use.
Frequently asked questions
Is this calculator for US gallons or UK gallons?
This tool uses US gallons, which is standard for MPG calculations in the United States.
Can I use this for diesel vehicles?
Yes. The MPG math is the same. The CO₂ estimate shown is based on gasoline and should be treated as a rough approximation for non-gasoline fuels.
How often should I calculate MPG?
Tracking every fill-up gives the clearest picture. Monthly tracking is also useful if you just want trends.
Final thoughts
A miles to the gallon calculator is one of the simplest ways to understand your driving efficiency and control fuel costs. Even small MPG improvements can add up to meaningful savings over a year. Use this tool consistently, track your numbers, and make small driving and maintenance changes to get better results over time.