How do I calculate my MPG?

Divide the miles driven by the gallons of gas used. For example, if you drove 300 miles on 10 gallons, your MPG is 30 (300 ÷ 10 = 30).

25-30 MPG is considered good for most vehicles. 35+ MPG is excellent. However, this varies by vehicle type - trucks and SUVs typically get lower MPG than sedans.

Why is my MPG lower than expected?

Common causes include under-inflated tires, aggressive driving, excessive idling, dirty air filter, faulty oxygen sensor, or needing a tune-up.

Does AC affect gas mileage?

Yes, AC can reduce MPG by 5-25% depending on conditions. At highway speeds, AC is more efficient than open windows which cause drag.

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MPG Calculator

Gas Mileage Calculator

Calculate your vehicle's fuel efficiency, see how you compare to expectations, and get tips to improve your MPG.

Calculate Your MPG

Enter your trip details to calculate fuel efficiency

Miles Driven *

Gallons Used *

gal

Gas Price (optional)

/gal

Expected MPG (optional)

MPG

Check your window sticker or fueleconomy.gov

Tips to Improve Fuel Efficiency

Simple changes that can boost your MPG

Maintain Steady Speed

+5-10% MPG

Use cruise control on highways. Rapid acceleration and braking can reduce MPG by 15-30%.

Check Tire Pressure

+3-5% MPG

Under-inflated tires increase rolling resistance. Check pressure monthly.

Remove Excess Weight

+1-2% MPG

Every 100 lbs reduces efficiency by about 1%. Remove unnecessary items from your trunk.

Replace Air Filter

+2-4% MPG

A dirty air filter can reduce fuel efficiency. Replace every 15,000-30,000 miles.

Reduce Idling

+5-10% MPG

Idling gets 0 MPG. Turn off the engine if stopped for more than 60 seconds.

Use Recommended Fuel

+0-3% MPG

Using premium when regular is recommended doesn't improve MPG and wastes money.

Concerned About Your Fuel Economy?

Our AI assistant can help diagnose issues that may be hurting your MPG and suggest maintenance that could improve efficiency.

Frequently Asked Questions

Common questions about fuel efficiency

How do I calculate MPG?

Divide miles driven by gallons used. Example: 300 miles ÷ 10 gallons = 30 MPG.

What's a good MPG?

25-30 MPG is good for most cars. 35+ is excellent. Trucks/SUVs typically get 15-22 MPG.

Why is my MPG low?

Common causes: under-inflated tires, aggressive driving, dirty air filter, or maintenance needed.

Does AC affect MPG?

Yes, AC can reduce MPG by 5-25%. At highway speeds, AC is more efficient than open windows.

Note: MPG calculations are estimates based on the data you provide. Actual fuel economy varies based on driving conditions, vehicle maintenance, and other factors. For official fuel economy ratings, visit fueleconomy.gov.