How to Convert Fuel Consumption
Enter the fuel consumption value in the Value field.
Select the unit you are converting from in the From list.
Select the unit you want to convert to in the To list.
The result appears instantly below the unit selectors.
Key Features
Efficiency and Consumption Formats
Handles both distance-per-volume units (km/L, mpg — higher means more efficient) and volume-per-distance units (L/100km, gal/mile — lower means more efficient), converting correctly between them.
37 Units Covered
Includes metric (km/L, L/100km), US and UK imperial (mpg, gal/mile), nautical, and a full range of volumetric combinations down to fluid ounces, cups, pints, and cubic inches.
Works Offline
All conversions run entirely in your browser using JavaScript. No internet connection is needed after the page loads.
Privacy-First
No data is ever sent to a server. Your values stay on your device.
Privacy & Security
This tool runs entirely in your browser. No values are transmitted to any server, stored, or logged. It is safe to use in offline environments.
Frequently Asked Questions
What is the difference between km/L and L/100km?
km/L (kilometers per liter) is an efficiency unit — higher means more fuel-efficient. L/100km (liters per 100 kilometers) is a consumption unit — lower means more fuel-efficient. They are reciprocals: L/100km = 100 ÷ (km/L value).
How does the converter handle efficiency vs consumption units?
Internally, all values are converted through a common base unit (meter per liter). Efficiency units (km/L, mpg) multiply by their factor to reach the base. Consumption units (L/100km, gal/mile) use the reciprocal relationship: base = 1 ÷ (value × factor).
What is the difference between US and UK gallons?
A US gallon is approximately 3.785 liters, while a UK (imperial) gallon is approximately 4.546 liters. This makes UK mpg figures higher than US mpg for the same vehicle — a car rated at 40 US mpg is approximately 48 UK mpg.
Why does converting 0 produce an error for some units?
Consumption units like L/100km represent volume per distance, so a value of 0 would mean infinite efficiency — which is undefined. The converter returns an error for these cases to avoid displaying a meaningless infinity result.
What base unit is used for the conversion?
All conversions pass through meter per liter (m/L) as the internal base unit. Each unit is stored as its exact multiplier relative to m/L, allowing any pair of units to be converted without a lookup table.