Mileage Calculator
Quickly convert fuel economy between MPG (US), MPG (UK), kilometers per liter, and liters per 100km. Free online mileage converter with comparison charts.
About This Calculator
The Fuel Economy Converter (also known as the Mileage Calculator) lets you instantly convert between all major fuel economy units: miles per US gallon (MPG US), miles per UK gallon (MPG UK), kilometers per liter (km/L), and liters per 100 kilometers (L/100km). Simply enter any one value and the calculator automatically computes the equivalents in all other units.
Fuel economy measures how efficiently a vehicle uses fuel. In the United States, fuel economy is expressed in miles per US gallon (MPG), where a higher number means better efficiency. The United Kingdom uses miles per imperial gallon (MPG UK), while most other countries including India, Australia, and European nations use liters per 100 kilometers (L/100km) where a lower number indicates better efficiency. Kilometers per liter (km/L) is another common metric used in many parts of the world.
The conversion uses the following standard formulas: 1 US gallon = 3.7854 liters, 1 UK gallon = 4.5461 liters, and 1 mile = 1.6093 kilometers. To convert MPG (US) to L/100km, divide 235.21 by the MPG value. For MPG (UK) to L/100km, divide 282.48 by the MPG value. To convert km/L to MPG (US), multiply by 2.352.
Regional Notes
India: Fuel economy is typically expressed in km/L for two-wheelers and passenger cars. The average fuel economy for Indian cars ranges from 15-25 km/L. The conversion to L/100km is common for European car imports.
United States: MPG (US) is the standard unit displayed on vehicle window stickers by the EPA. Average fuel economy for new cars in the US is approximately 25 MPG. The US gallon (3.785 L) differs from the imperial gallon used in the UK.
United Kingdom: MPG (UK) using the imperial gallon (4.546 L) is standard on UK vehicles. However, L/100km is also commonly listed in vehicle specifications. Average fuel economy for UK cars is around 40-50 MPG (UK) for diesel vehicles and 35-45 MPG (UK) for petrol vehicles.
Frequently Asked Questions
How do I convert MPG to L/100km?
To convert MPG (US) to L/100km, divide 235.21 by the MPG value. For example, 25 MPG (US) equals 235.21 ÷ 25 = 9.41 L/100km. For MPG (UK), divide 282.48 by the MPG value instead.
What is the difference between US MPG and UK MPG?
US MPG uses the US gallon (3.785 liters) while UK MPG uses the imperial gallon (4.546 liters). One US MPG equals approximately 1.201 UK MPG, and one UK MPG equals about 0.833 US MPG. The UK gallon is about 20% larger than the US gallon.
How do I calculate km/L from MPG?
To convert MPG (US) to km/L, multiply the MPG value by 0.4251. For example, 25 MPG (US) × 0.4251 = 10.63 km/L. For MPG (UK), multiply by 0.3540 instead to get km/L.
What is a good fuel economy in L/100km?
A fuel economy of under 6 L/100km (about 39 MPG US) is considered excellent. Between 6-8 L/100km (29-39 MPG) is good for most modern cars. SUVs and larger vehicles typically range from 8-12 L/100km (20-29 MPG). Electric vehicles have an equivalent of 1.5-2.5 L/100km.
Is this fuel economy converter free to use?
Yes, it is completely free to use with no registration required. You can share your conversion results via the URL, which saves all your input values for easy sharing.
What fuel economy units are commonly used in different countries?
The United States uses MPG (US gallons). The United Kingdom and Canada use MPG (imperial/UK gallons). Most other countries including India, Australia, and European nations use L/100km or km/L. This converter supports all four major units.
How accurate is the fuel economy conversion?
The conversion uses precise mathematical formulas based on the standard conversion factors: 1 US gallon = 3.7854 L, 1 UK gallon = 4.5461 L, and 1 mile = 1.6093 km. Results are accurate to two decimal places.