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Fuel Economy Tool

MPG Calculator

Calculate your vehicle's US MPG, UK MPG, L/100km, km/L, total fuel cost, and cost per 100 miles.

Fuel Economy Calculator

Enter your trip distance and fuel consumption.

Private calculation

Trip information

Use the distance from your trip meter or odometer.
Enter the amount needed to refill the fuel tank.
Add a price to estimate trip fuel cost.

Instant results

Your fuel economy is calculated immediately.

Multiple units

Use miles, kilometers, liters, or gallons.

No data stored

Your information stays inside your browser.

What is an MPG calculator?

An MPG calculator determines how many miles your vehicle travels for each gallon of fuel it consumes. MPG stands for miles per gallon. A higher MPG value generally means the vehicle uses less fuel to travel the same distance.

You can calculate fuel economy by recording the distance traveled and the amount of fuel required to refill your tank. This tool converts those figures into US MPG, UK MPG, liters per 100 kilometers, and kilometers per liter.

Why monitor fuel economy?

Tracking MPG can help you estimate travel expenses, compare vehicles, plan a road trip, and identify changes in vehicle performance. A sudden drop in fuel economy may indicate low tire pressure, aggressive driving, excess weight, or a mechanical issue.

US MPG and UK MPG are different

A UK imperial gallon is larger than a US liquid gallon. Therefore, the UK MPG result will be higher than the US MPG result for the same vehicle and fuel consumption.

Simple process

How to use the MPG calculator

Calculate your vehicle's fuel economy in three straightforward steps.

01

Enter your distance

Add the distance traveled and select miles or kilometers.

02

Add the fuel used

Enter the fuel consumed in US gallons, UK gallons, or liters.

03

View the results

See US MPG, UK MPG, L/100km, km/L, and estimated fuel cost.

Fuel-saving guidance

Ways to improve your vehicle's MPG

Small changes in driving and maintenance can reduce fuel consumption.

Drive smoothly

Avoid unnecessary hard acceleration and sudden braking.

Check tire pressure

Properly inflated tires can reduce rolling resistance.

Remove excess weight

Carrying unnecessary cargo makes the engine work harder.

Maintain your vehicle

Follow recommended oil, filter, tire, and service schedules.

Common questions

MPG calculator FAQs

Helpful answers about mileage, gallons, and fuel economy.

Divide the number of miles traveled by the number of gallons used. For example, 300 miles divided by 10 US gallons equals 30 US MPG.

Good MPG depends on vehicle type, engine size, driving conditions, and model year. Smaller cars and hybrid vehicles usually achieve higher MPG than large trucks and SUVs.

The UK imperial gallon contains about 4.546 liters, while a US gallon contains about 3.785 liters. Because the UK gallon is larger, UK MPG figures are higher.

A higher MPG is generally better because the vehicle travels farther on each gallon of fuel. For L/100km, however, a lower number is better.

Advertised figures are produced under standardized testing conditions. Real-world results can change due to traffic, speed, weather, tire pressure, vehicle load, maintenance, and driving habits.

Fill the tank completely, reset the trip meter, drive normally, and refill at the same station or pump. Use the trip distance and the exact refill amount in the calculator.

Note: This calculator provides estimates for informational purposes. Vehicle dashboards, pumps, odometers, and fuel prices may contain small measurement differences.