Free Online Fuel Efficiency Converter — km/L, MPG, and L/100km
Fuel efficiency converter that instantly translates mileage between km/L, MPG (US and UK), and L/100km. Compare your vehicle's fuel economy across Indian, American, European, and British measurement standards — entirely in your browser.
Convert Your Fuel Efficiency
How to Use This Fuel Efficiency Converter
Enter Your Fuel Efficiency Value
Type the numeric mileage or fuel consumption value you want to convert into the input field. For example, enter 18.5 if your car achieves 18.5 km/L.
Select the Input Unit
Choose the unit your value is currently in from the dropdown — kilometres per litre, litres per 100 km, miles per US gallon, or miles per Imperial gallon.
Click Convert
Press the Convert button or hit Enter. All equivalent fuel efficiency values across every supported unit will appear instantly.
Review All Converted Values
Compare your vehicle's mileage across Indian (km/L), European (L/100km), American (MPG US), and British (MPG UK) standards in the results panel.
Copy Any Result
Click the copy icon next to any individual result to copy that value to your clipboard for use in documents, comparisons, or vehicle listings.
Key Features of Fuel Efficiency Converter
100% Free Conversions
Convert between all fuel efficiency units unlimited times with no charges, account requirements, or premium restrictions whatsoever.
Supports km/L, MPG, and L/100km
Covers every major fuel economy standard — Indian km/L, US MPG, UK Imperial MPG, and European L/100km in one tool.
Instant Real-Time Results
Conversions compute in under a millisecond using precise mathematical constants — no waiting, no loading, no server round-trips.
Indian and International Units
Designed for Indian car buyers comparing ARAI mileage with US EPA or European WLTP figures across global vehicle models.
Complete Browser Privacy
All calculations run locally in your browser's JavaScript engine. No fuel data is transmitted, logged, or stored anywhere.
Works on All Devices
Fully responsive design adapts to phones, tablets, and desktops — convert fuel efficiency on the go from any device or browser.
How Fuel Efficiency Conversion Works
km/L × 2.35215 = MPG (US) km/L × 2.82481 = MPG (UK) 100 ÷ km/L = L/100kmConversion Constants Used
For example, a Hyundai i20 with an ARAI mileage of 20.35 km/L converts to: L/100km = 100 ÷ 20.35 = 4.91, MPG US = 20.35 × 2.35215 = 47.87, and MPG UK = 20.35 × 2.82481 = 57.48. This means an Indian car rated at ~20 km/L would be considered a ~48 MPG vehicle in the American market.
Assumptions: All conversions use exact standard conversion factors at standard conditions. Real-world mileage varies by driving style, road conditions, elevation, temperature, AC usage, and vehicle load. The converted values represent the mathematical equivalent, not a guarantee of real-world performance across different testing standards (ARAI, EPA, WLTP).
Practical Examples
Maruti Suzuki Swift — Indian City Car
Input: 22 km/L (ARAI certified)
Result: 4.55 L/100km | 51.75 MPG US | 62.15 MPG UK
Use Case: A buyer in Mumbai comparing the Swift's mileage against European hatchbacks listed in L/100km on international review sites.
Honda City — Indian Sedan
Input: 17.8 km/L (ARAI certified)
Result: 5.62 L/100km | 41.87 MPG US | 50.28 MPG UK
Use Case: A Delhi resident checking whether the Honda City's fuel economy matches competing sedans listed in US MPG on global comparison websites.
Ford F-150 — American Pickup Truck
Input: 25 MPG US (EPA highway rating)
Result: 10.63 km/L | 9.41 L/100km | 30.02 MPG UK
Use Case: An NRI in the US comparing their truck's efficiency against the Indian vehicles their family drives back home, bridging the MPG-to-km/L gap.
Volkswagen Golf — European Compact
Input: 5.5 L/100km (WLTP combined)
Result: 18.18 km/L | 42.77 MPG US | 51.36 MPG UK
Use Case: A car enthusiast in Bangalore researching European-market vehicles and needing km/L figures to compare against Indian-market alternatives.
What Is the Fuel Efficiency Converter?
The fuel efficiency converter is a browser-based utility that translates fuel economy values between four major global measurement systems: kilometres per litre (km/L) used in India and Japan, litres per 100 kilometres (L/100km) used across Europe, miles per US gallon (MPG US) used in the United States, and miles per Imperial gallon (MPG UK) used in the United Kingdom.
This tool serves anyone who needs to compare vehicle mileage across different regional standards:
- Indian car buyers comparing ARAI mileage with international review figures
- NRIs evaluating fuel costs between vehicles in India and abroad
- Automotive journalists and bloggers converting specs for cross-market articles
- Fleet managers operating vehicles across countries with different standards
- Used car importers translating foreign vehicle specifications for Indian buyers
The most common scenario in India involves converting a car's ARAI-rated km/L figure into MPG or L/100km when reading international car reviews, or the reverse — understanding what a 40 MPG US rating means in km/L terms familiar to Indian drivers.
Sources and Methodology
All conversions use internationally standardised constants: the US liquid gallon defined as exactly 3.78541 litres, the Imperial gallon as 4.54609 litres, and the statute mile as 1.60934 kilometres. These are the same conversion factors used by automotive regulatory bodies including ARAI in India, the US EPA, and the European Commission for their respective fuel economy standards.
Important Considerations
Different countries test fuel efficiency under different protocols — India uses the ARAI-modified Indian Driving Cycle, the US uses the EPA's five-cycle test, and Europe uses the WLTP standard. A car rated 20 km/L under ARAI testing may not deliver the exact equivalent of 47 MPG under EPA testing because the test conditions differ. This converter provides the precise mathematical unit conversion, not a cross-standard test equivalency. For purchasing decisions, always compare vehicles tested under the same protocol and account for the 15–30% gap between lab ratings and real-world driving.
Frequently Asked Questions
Yes, this converter is 100% free with no hidden charges, no signup, and no premium features. Every conversion between km/L, MPG, and L/100km is fully available at zero cost with unlimited use.
Absolutely. All conversions are calculated entirely in your browser using JavaScript. No values are sent to any server, stored in any database, or shared with anyone. Your data stays on your device only.
Conversions use precise standard conversion factors: 1 US gallon equals 3.78541 litres, 1 Imperial gallon equals 4.54609 litres, and 1 mile equals 1.60934 km. Results are accurate to two decimal places, matching the precision used by automotive manufacturers.
The US gallon is 3.78541 litres while the Imperial (UK) gallon is 4.54609 litres — about 20% larger. So the same car will have a higher MPG number in UK units than US units. A car rated at 40 MPG US would be about 48 MPG UK.
India, like Japan and many Asian countries, expresses mileage as distance per unit fuel (km/L) — higher is better. Europe uses fuel consumed per distance (L/100km) — lower is better. Both measure the same thing from opposite perspectives. This converter bridges both conventions instantly.
Enter the ARAI-certified km/L figure in this converter, select km/L as the input unit, and click Convert. The tool shows the MPG US and MPG UK equivalents instantly. For example, an ARAI rating of 20 km/L equals approximately 47.04 MPG US.
No. ARAI (Automotive Research Association of India) tests are conducted under controlled laboratory conditions. Real-world mileage typically falls 15-30% below the ARAI figure depending on driving style, traffic, terrain, AC usage, and vehicle load. Use the ARAI figure for relative comparison between vehicles.
For petrol cars in Indian city driving, 12-15 km/L is average, 15-20 km/L is good, and above 20 km/L is excellent. Diesel cars typically achieve 15-25 km/L. Hybrid vehicles like the Maruti Grand Vitara can exceed 25 km/L in city conditions.
This converter handles traditional fuel efficiency units only (km/L, L/100km, MPG). Electric vehicles use different metrics like kWh/100km or km/kWh which measure electricity consumption rather than liquid fuel. A dedicated EV efficiency tool would be needed for those conversions.
Enter either car's mileage in its native unit — km/L for the Indian car or MPG US for the American car. The converter displays both values in every unit side by side, making direct comparison simple. Remember that US EPA figures also differ from real-world driving, similar to ARAI ratings.