Gas Mileage Calculator
What is a gas mileage calculator? Calculate MPG from distance and fuel used, then compare fuel cost, consumption, and vehicle efficiency.
Interactive inputs
Live result
30.00
MPG
Change an input to update the diagram.
Answer first
What is a gas mileage calculator?
The Gas Mileage Calculator is the definitive tool for measuring your vehicle's fuel efficiency. Enter distance traveled, fuel consumed, and fuel price to see your MPG, fuel cost per mile, and total trip cost. It serves anyone who fills up a car, truck, or SUV and wants to know exactly how far each gallon takes them.
Current calculator output
30.00
MPG
How it works
Gas Mileage Calculator: inputs, formula, and result
This straightforward tool takes the exact distance you traveled between fill-ups and divides it by the total gallons needed to refill the tank. It outputs the fundamental miles per gallon figure that reflects your vehicle's current real-world efficiency.
Formula
MPG = Distance ÷ Fuel Used; Cost Per Mile = Fuel Price ÷ MPG
Worked example
360 miles on 30 gallons at $3.50/gallon: MPG = 12. Cost per mile = $0.292.
Pro tip: Use the tank-to-tank method: fill up completely, reset your trip odometer, drive normally, fill up again, and divide miles by gallons added.
Personalized guidance
What changes the result for Gas Mileage?
Your calculated mileage is directly affected by traffic conditions, ambient weather, aggressive acceleration, tire pressure, and the quality of the fuel pumped. Traffic, tire pressure, vehicle load, terrain, driving style, weather, fuel price, and the quality of the input data can change the final result.
Estimated result condition
100%
Select factors that match this high priority calculation.
When should you use this calculator?
Keep this tool handy for tracking everyday driving efficiency after every trip to the gas station. It serves as an early warning system for mechanical issues; a sudden, unexplained drop in gas mileage often indicates a failing sensor or underinflated tires.
Selected usePlan with Gas Mileage Calculator
FAQ
FAQs about Gas Mileage
3 questions
Question 1 of 3 is open
How do I calculate gas mileage accurately?
Fill your tank completely, note the odometer, drive normally, fill up again. Divide miles driven by gallons added. Repeat over 3-5 fill-ups and average the results.
What factors most affect gas mileage?
Driving speed (optimal 45-65 mph), acceleration style (gentle is 10-33% better), vehicle weight, tire pressure, AC use, engine maintenance, and weather (cold reduces MPG 10-20%).
Why is my gas mileage getting worse?
Common causes: underinflated tires (-3-5%), dirty air filter (-up to 10%), worn spark plugs (-up to 5%), faulty oxygen sensor (-up to 40%), or more city driving.
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