A fuel economy converter translates between the different units used worldwide to measure vehicle fuel efficiency. The United States uses miles per gallon (MPG), Europe and Australia use liters per 100 kilometers (L/100km), and Japan uses kilometers per liter (km/L). This tool converts between all four standards instantly and shows how your vehicle compares to common benchmarks.
Enter Fuel Economy
Common Vehicle Reference
| Vehicle Type | MPG (US) | MPG (Imp.) | L/100km | km/L |
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Quick Conversion Chart
| MPG (US) | MPG (Imp.) | L/100km | km/L |
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How to Use the Fuel Economy Converter
Different countries measure fuel economy in different ways, making it confusing to compare vehicles across borders. This free fuel economy converter instantly translates between MPG (US), MPG (Imperial), L/100km, and km/L, so you can compare any vehicle's efficiency regardless of where it was rated.
Step 1: Enter a Value
Type the fuel economy value you want to convert. This can be the EPA rating from a US vehicle sticker, a European specification in L/100km, or any other fuel economy number you have. The converter accepts decimal values for precise conversions.
Step 2: Select the Source Unit
Choose which unit your value is in from the dropdown. MPG (US) uses the US gallon of 3.785 liters. MPG (Imperial) uses the UK gallon of 4.546 liters, which is about 20% larger. L/100km measures liters of fuel consumed per 100 kilometers. km/L measures how many kilometers you travel per liter of fuel.
Step 3: View All Conversions
Click Convert to see the equivalent value in all four units simultaneously. The results appear in clear stat cards so you can quickly find the unit you need. Remember that MPG and km/L are "higher is better" scales, while L/100km is "lower is better" since it measures consumption rather than distance.
Understanding the Efficiency Rating
The fuel economy efficiency rating puts your value in context by comparing it to typical vehicle performance ranges. Ratings range from "Poor" (under 15 US MPG, typical of older trucks) through "Average" (20-25 MPG, a typical sedan) to "Outstanding" (40+ MPG, achieved by modern hybrids). This helps you quickly understand whether a vehicle's fuel economy is competitive.
Vehicle Reference Table
The common vehicle reference table shows typical fuel economy values for different vehicle categories including compact sedans, midsize sedans, SUVs, pickup trucks, hybrids, and electric vehicles (measured in MPGe). Use this table to understand how a specific vehicle compares to its segment and to get a sense of real-world fuel economy expectations.
US vs Imperial Gallons
One of the most common sources of confusion in fuel economy is the difference between US and Imperial gallons. A US gallon equals 3.785 liters, while an Imperial gallon equals 4.546 liters. This means a car rated at 30 MPG in the US would show as about 36 MPG using Imperial gallons. Always check which gallon standard is being used when comparing vehicles from different markets.
FAQ
Is this fuel economy converter free to use?
Yes, this fuel economy converter is completely free with no limits. Convert between MPG, L/100km, and km/L as many times as you need without signing up or paying anything.
Is my data safe when using this tool?
Absolutely. All calculations run entirely in your browser using JavaScript. No data is ever sent to a server. The tool works completely offline once the page loads.
What is the difference between US MPG and Imperial MPG?
US MPG and Imperial MPG use different gallon sizes. A US gallon is 3.785 liters while an Imperial gallon is 4.546 liters. This means Imperial MPG numbers are always about 20% higher than US MPG for the same vehicle. This converter handles both standards.
How do I convert MPG to L/100km?
To convert US MPG to L/100km, divide 235.215 by the MPG value. For example, 30 US MPG equals 235.215 / 30 = 7.84 L/100km. For Imperial MPG, divide 282.481 by the MPG value. This converter does the math for you instantly.
What is a good fuel economy rating?
A good fuel economy for a gasoline car is 25-30 MPG (US) or 7.8-9.4 L/100km. Excellent economy is 30-40 MPG or 5.9-7.8 L/100km. Hybrid vehicles typically achieve 40-60 MPG. The efficiency rating in this tool provides context for any value you enter.
Why does L/100km go up when fuel economy improves?
L/100km actually goes down when fuel economy improves, because it measures consumption rather than distance. Lower L/100km means less fuel used, which is better. This is the opposite of MPG where higher is better. 5 L/100km is more efficient than 10 L/100km.
What fuel economy unit does my country use?
The US uses MPG (US gallons). The UK uses MPG (Imperial gallons). Most of Europe, Australia, and many other countries use L/100km. Japan and some Asian countries use km/L. This converter supports all four standards so you can compare across regions.
How accurate is this converter?
This converter uses the exact mathematical conversion factors between units and is accurate to multiple decimal places. The conversion constants are: 235.215 for US MPG to L/100km and 282.481 for Imperial MPG to L/100km.