Gas Mileage Calculator

Fuel Economy Tips

Drive Efficiently

Avoid aggressive acceleration. Every 5 mph over 50 costs more fuel.

Maintain Your Vehicle

Keep tires properly inflated and engine tuned for best MPG.

Average MPG by Type

Compact Car30-40 MPG
Sedan25-35 MPG
SUV20-28 MPG
Truck15-22 MPG

Understanding Fuel Economy

How to Calculate MPG

Miles per gallon (MPG) measures how far your vehicle can travel on one gallon of fuel. Higher MPG means better fuel efficiency and lower fuel costs.

MPG Formula

MPG = Miles Driven ÷ Gallons Used
Example: 300 miles ÷ 10 gallons = 30 MPG

Factors Affecting Fuel Economy

Decreases MPG

  • Aggressive acceleration
  • Speeding (over 50 mph)
  • Excessive idling
  • Under-inflated tires
  • Heavy cargo
  • Using A/C at low speeds

Increases MPG

  • Smooth acceleration
  • Maintaining steady speed
  • Proper tire inflation
  • Regular maintenance
  • Removing excess weight
  • Windows up at highway speed

MPG vs L/100km

The US uses MPG (higher is better), while most other countries use liters per 100 kilometers (lower is better).

MPG (US)L/100kmRating
504.7Excellent
356.7Good
259.4Average
1515.7Poor

Money-Saving Tips

  • Every 5 mph over 50 is like paying an extra $0.20/gallon
  • Proper tire pressure can improve MPG by up to 3%
  • Removing 100 lbs of cargo improves MPG by about 1%
  • A well-tuned engine can improve MPG by up to 4%
  • Use cruise control on highways to maintain steady speed

Frequently Asked Questions

How do I calculate my car's MPG?

Fill your tank completely, reset your trip odometer, drive normally until you need gas again, then divide miles driven by gallons used. Formula: MPG = Miles Driven / Gallons Used. For accuracy, repeat over several fill-ups.

What is considered good gas mileage?

Good gas mileage varies by vehicle type. Compact cars: 30-40 MPG is good, 40+ is excellent. SUVs: 25-30 MPG is good. Trucks: 20-25 MPG is good. Hybrids typically achieve 45-60 MPG, while EVs equivalent can exceed 100 MPGe.

Why is my MPG lower than the EPA estimate?

EPA tests are conducted under controlled conditions. Real-world factors that lower MPG include aggressive driving, speeding, city driving with frequent stops, cold weather, using AC, under-inflated tires, and carrying heavy loads.

How can I improve my gas mileage?

Drive smoothly without rapid acceleration, maintain 55-65 MPH on highways, keep tires properly inflated (can improve MPG by 3%), remove excess weight, use cruise control, avoid excessive idling, and keep up with regular maintenance.