Mile Per Gallon (MPG) Calculator
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Your Fuel Efficiency: 0 MPG
Cost Per Mile: 0
Total Fuel Cost: 0
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How to Calculate Miles Per Gallon (MPG)
Understanding your vehicle's fuel efficiency is crucial for budgeting and monitoring your car's health. The basic formula for calculating MPG is straightforward: divide the total miles driven by the number of gallons used to refill the tank.
The Formula: Miles Driven / Gallons Used = MPG
Steps to Get an Accurate Reading
- Fill Your Tank: Fill your gas tank completely and record your current odometer reading (or reset your trip odometer).
- Drive Regularly: Use your car as you normally would until the tank is at least half empty.
- Refill and Record: Go back to the gas station, fill the tank completely again, and note down two numbers: the miles traveled since the last fill-up and the exact number of gallons it took to refill the tank.
- Calculate: Use the tool above or the formula to find your fuel economy.
Real-World MPG Examples
- Example 1 (Commuter Car): If you drive 400 miles and use 12 gallons of fuel, your efficiency is 33.33 MPG.
- Example 2 (Heavy SUV): If you drive 300 miles and use 20 gallons of fuel, your efficiency is 15.00 MPG.
- Example 3 (Hybrid): If you drive 550 miles and use 10 gallons of fuel, your efficiency is 55.00 MPG.
Factors That Affect Your Fuel Economy
Several variables can cause your MPG to fluctuate from week to week:
- Driving Habits: Rapid acceleration and hard braking significantly reduce efficiency.
- Tire Pressure: Under-inflated tires increase rolling resistance, making the engine work harder.
- Vehicle Load: Carrying extra weight (like tools or cargo) lowers your mileage.
- Air Conditioning: Running the AC at max power consumes more engine power and fuel.
- Maintenance: Old spark plugs, dirty air filters, or clogged fuel injectors can degrade performance.