Fuel Economy Converter
Convert any fuel economy unit to another with this free fuel economy converter. It supports 4 units including kilometers per liter, miles per us gallon, miles per uk gallon, liters per 100 kilometers. Pick a conversion below for a dedicated calculator, formula, and reference table. For example, 1 km/L = 2.3521458 mpg.
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About these units
Kilometer per Liter (km/L)
- Definition
- Kilometers per liter (km/L) is a metric fuel-economy measure expressing how far a vehicle travels on one liter of fuel.
- History
- It entered common use in Asia and parts of Europe as fuel taxation and efficiency standards spread.
- Current use
- Km/L is the standard fuel-economy unit in Japan, India, and many other Asian markets.
Mile per US Gallon (mpg)
- Definition
- Miles per US gallon (mpg) expresses how far a vehicle travels per US gallon (3.785 L) of fuel.
- History
- The US gallon-based mpg has been the standard US fuel-efficiency measure since the Corporate Average Fuel Economy (CAFE) standards began in 1975.
- Current use
- Every new car sold in the United States lists its EPA fuel-economy rating in city/highway/combined mpg.
Mile per UK Gallon (mpg UK)
- Definition
- Miles per imperial gallon (mpg UK) uses the larger UK gallon (4.546 L), so UK mpg figures are higher than US mpg for the same vehicle.
- History
- The United Kingdom standardised on imperial gallons until adopting metric fuel labels in recent decades.
- Current use
- Imperial mpg still appears in older UK car reviews and some Commonwealth markets; modern UK regulation uses L/100km.
Liter per 100 Kilometers (L/100km)
- Definition
- Liters per 100 kilometers (L/100km) measures fuel consumption as the volume of fuel needed to travel 100 km — lower is more efficient.
- History
- It became the European Union standard fuel-consumption metric and appears on all new cars sold in the EU, Australia, and Canada.
- Current use
- L/100km is the mandatory label on EU, Australian, and Canadian new-car fuel economy stickers.
Frequently asked questions
What fuel economy units can I convert?
This fuel economy converter supports 4 units: kilometers per liter, miles per us gallon, miles per uk gallon, liters per 100 kilometers. Select any pair below to open a dedicated converter with a formula and conversion table.
How accurate is the fuel economy converter?
Conversions use exact definitional factors, so results are accurate to the precision you need for science, engineering, and everyday use. Values are rounded only for display.
Is the fuel economy converter free?
Yes. Every fuel economy conversion is completely free, needs no sign-up, and runs entirely in your browser — your inputs never leave your device.
Free, private, and instant — every conversion runs in your browser.
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