Authoritative definitions of the International System of Units and SI prefixes.
Unit converters
Fuel efficiency
Enter your values below for a clear, instant result.
Fuel consumption & efficiencyInstant result
Decimals
Formula Convert L/100 km to litres per 100 kilometres, then convert to mpg (US). 1 L/100 km = 235.2146 mpg (US)
Common examples
One value, several units
Miles per US gallon235.2146 mpg (US)
Miles per imperial gallon282.4809 mpg (imp)
Kilometres per litre100 km/L
Conversion table
| L/100 km | mpg (US) |
|---|---|
| 1 L/100 km | 235.2146 mpg (US) |
| 2 L/100 km | 117.6073 mpg (US) |
| 5 L/100 km | 47.0429 mpg (US) |
| 10 L/100 km | 23.5215 mpg (US) |
| 25 L/100 km | 9.4086 mpg (US) |
| 50 L/100 km | 4.7043 mpg (US) |
| 100 L/100 km | 2.3521 mpg (US) |
Conversion chart
1 L/100 km235.2146 mpg (US)
5 L/100 km47.0429 mpg (US)
10 L/100 km23.5215 mpg (US)
25 L/100 km9.4086 mpg (US)
50 L/100 km4.7043 mpg (US)
Worked example
8 L/100 km is approximately 29.4 US mpg.
Unit definition
Litres per 100 kilometres (L/100 km) This unit is defined through the displayed non-linear relationship to litres per 100 kilometres.
Unit history
Litres per 100 kilometres is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert L/100 km to litres per 100 kilometres.
3. Convert the base value to mpg (US) and apply your display precision.
Important
Fuel economy and fuel consumption are reciprocal measures; zero is not a valid input.
Understand the result before using it
Fuel efficiency switches between reciprocal fuel-consumption and fuel-economy conventions. The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
Convert L/100 km to litres per 100 kilometres, then convert the base value to mpg (US).
Assumptions
- The source and target selections represent the same physical quantity or supported notation.
- The entered value is valid for the selected relationship and uses the source unit shown.
- Fuel economy and fuel consumption are reciprocal measures; zero is not a valid input.
Worked example
8 L/100 km is approximately 29.4 US mpg.
When to use it
Good uses
- Translate a fuel efficiency value found in a document, specification, recipe, or measurement.
- Compare values reported in different unit systems.
- Check a manual conversion and control the displayed precision.
Limitations
Common mistakes to avoid
- Fuel consumption and fuel economy are reciprocal; zero and negative values are not physically valid inputs.
- Do not add meaningful digits beyond the precision of the original measurement.
- Confirm regulated, safety-critical, laboratory, and contractual values against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
What does the Fuel efficiency converter do?
Fuel efficiency switches between reciprocal fuel-consumption and fuel-economy conventions. It does not change the physical quantity represented by the input.
What formula does the Fuel efficiency converter use?
Convert L/100 km to litres per 100 kilometres, then convert the base value to mpg (US).
Why can a Fuel efficiency converter result be rounded?
UnitMora calculates with JavaScript double-precision numbers, then formats the result using your selected decimal or significant-figure setting. The unrounded value may contain more digits than are displayed.
What is the most common fuel efficiency conversion mistake?
Fuel consumption and fuel economy are reciprocal; zero and negative values are not physically valid inputs.
Clear answers, without the guesswork
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