MPG Calculator
Calculate your vehicle's fuel efficiency in miles per gallon (MPG) and estimate your fuel costs. Track your gas mileage, compare vehicles, and plan your driving budget with our free, easy-to-use MPG calculator.
What Is MPG?
MPG (Miles Per Gallon) is a measure of fuel efficiency that indicates how many miles a vehicle can travel on one gallon of fuel. Higher MPG means better fuel economy, you can drive further on less fuel, saving money and reducing emissions.
The standard formula for calculating MPG is:
MPG = Distance Driven (miles) ÷ Fuel Used (gallons)
For example: If you drive 300 miles and use 12 gallons of fuel:
MPG = 300 ÷ 12 = 25 MPG
Conversion: To convert MPG to L/100km, divide 235.215 by the MPG value.
25 MPG = 235.215 ÷ 25 = 9.4 L/100km
This calculator also helps you estimate fuel costs for individual trips and your annual driving budget based on your average MPG and fuel prices.
Fuel Efficiency Reference Table
| Vehicle Type | City MPG | Highway MPG | Combined MPG | L/100km |
|---|---|---|---|---|
| Compact Car | 28-32 | 36-42 | 30-35 | 7.8-6.7 |
| Midsize Sedan | 24-28 | 32-38 | 26-32 | 9.0-7.4 |
| SUV / Crossover | 20-24 | 26-31 | 22-27 | 10.7-8.7 |
| Pickup Truck | 15-19 | 19-24 | 16-21 | 14.7-11.2 |
| Hybrid | 50-55 | 45-50 | 48-52 | 4.9-4.5 |
| Electric Vehicle | 100-120 MPGe | 110 MPGe | N/A | N/A |
Tips to Improve Your MPG
- Maintain Proper Tire Pressure: Under-inflated tires can reduce MPG by up to 3%. Check monthly.
- Drive Smoothly: Aggressive acceleration and braking can lower MPG by 15-30% on highways.
- Reduce Speed: Each 5 mph over 50 mph costs an additional $0.20-$0.30 per gallon.
- Remove Excess Weight: Every 100 lbs reduces MPG by about 1%. Remove roof racks when not in use.
- Regular Maintenance: Clean air filters, fresh oil, and proper alignment improve efficiency by 4-10%.
- Use Cruise Control: Maintains a steady speed on highways, improving fuel economy by 4-14%.
❓ MPG Calculator FAQ
How do I calculate my car's MPG?
Fill your tank completely, record the odometer reading, drive normally, and refill the tank. Record the gallons used and the new odometer reading. MPG = (New Odometer − Old Odometer) ÷ Gallons Used. This calculator does this for you automatically.
What is a good MPG for a car?
A good MPG depends on the vehicle type. Compact cars typically get 30-35 MPG, SUVs get 22-27 MPG, and hybrids get 48-52 MPG. Generally, anything above 25 MPG is considered good for combined driving.
What is the difference between MPG and L/100km?
MPG (Miles Per Gallon) measures how many miles you can drive on one gallon of fuel. L/100km measures how many liters of fuel you need to drive 100 kilometers. Higher MPG and lower L/100km both indicate better fuel efficiency.
How do I convert MPG to L/100km?
To convert MPG to L/100km, divide 235.215 by the MPG value. For example, 25 MPG = 235.215 ÷ 25 = 9.4 L/100km. To convert L/100km to MPG, divide 235.215 by the L/100km value.
How does driving speed affect MPG?
Fuel efficiency generally decreases at speeds over 50 mph. Each 5 mph over 50 mph can cost an additional $0.20-$0.30 per gallon. Driving at 65 mph instead of 55 mph can reduce fuel economy by 10-15%.
How do I calculate fuel cost for a trip?
Fuel cost = (Distance ÷ MPG) × Fuel Price. For example, a 300-mile trip at 25 MPG with $3.50/gallon costs (300 ÷ 25) × $3.50 = $42.00. This calculator can estimate trip costs in both modes.
What is the average MPG for cars in the US?
The average fuel efficiency for new cars in the US is about 25 MPG (9.4 L/100km). However, this varies significantly by vehicle type. SUVs and trucks average around 20 MPG, while hybrids can exceed 50 MPG.
How can I improve my car's MPG?
You can improve MPG by maintaining proper tire pressure, driving smoothly, reducing speed, removing excess weight, keeping up with regular maintenance, and using cruise control on highways. These steps can improve MPG by 4-30%.
Does using the AC affect MPG?
Yes, using the air conditioner can reduce fuel efficiency by 5-10% in city driving and 2-4% on highways. At speeds over 40 mph, using AC is more efficient than driving with windows down, which creates aerodynamic drag.
What is the difference between city and highway MPG?
City MPG is measured in stop-and-go traffic conditions, which typically result in lower fuel efficiency due to frequent acceleration and braking. Highway MPG is measured at steady speeds on open roads, which usually gives higher fuel efficiency.
How do I calculate my annual fuel cost?
Annual fuel cost = (Annual Miles ÷ MPG) × Fuel Price. For example, if you drive 12,000 miles per year at 25 MPG with $3.50/gallon, your annual fuel cost is (12,000 ÷ 25) × $3.50 = $1,680.
What is the difference between regular and premium fuel?
Regular fuel (87 octane) is suitable for most vehicles. Premium fuel (91-93 octane) is recommended for high-performance engines. Using premium fuel in a car that doesn't require it does not improve performance or MPG.
How does tire pressure affect MPG?
Under-inflated tires increase rolling resistance, which reduces fuel efficiency. Properly inflated tires can improve MPG by up to 3%. Check your tire pressure monthly and keep them at the manufacturer's recommended PSI.
What is the difference between MPG and MPGe?
MPG measures fuel efficiency for gasoline vehicles. MPGe (Miles Per Gallon Equivalent) measures efficiency for electric vehicles, converting electrical energy consumption into an equivalent gallons of gasoline. 1 gallon of gasoline = 33.7 kWh of electricity.
How do I compare two vehicles using this calculator?
Enter your vehicle's MPG in the main calculation and the comparison vehicle's MPG in the "Compare with Vehicle" field in advanced options. The calculator will show how much you save or spend compared to the other vehicle.
How accurate is this MPG calculator?
This calculator provides accurate estimates based on standard formulas and the values you enter. Actual MPG may vary based on driving conditions, vehicle maintenance, and other factors. Use this as a planning tool for budgeting and vehicle comparison.
What is the best way to track my MPG over time?
Use this calculator regularly after each fill-up. Track your MPG across different driving conditions (city vs highway) and seasons. This helps you identify changes in fuel efficiency and address any maintenance issues early.