Fuel Efficiency Converter
Converts between litres per 100km (L/100km), miles per gallon (US MPG and UK MPG), km per litre and miles per litre. Also calculates fuel cost for a journey.
How to use the Fuel Efficiency Converter
Enter your input and the result appears instantly.
- Use the toolEnter values or paste content into the input area. Furthermore, all processing happens instantly in your browser.
- Read the outputResults appear immediately in the output panel. Moreover, copy buttons make it easy to use the output.
- Copy or downloadUse the copy button or save output to clipboard. Furthermore, no account or login is required.
- Adjust as neededModify inputs to refine the result. Moreover, all changes update output in real time.
- Use freelyLazyTools is free with no usage limits. Furthermore, no data is sent to any server — everything runs locally.
Options and variants explained
Feature overview.
| Feature | Description | Notes |
|---|---|---|
| Browser-based | No server required | Private and instant |
| Free | No account needed | Unlimited use |
| Output | Calculated result | Copy to clipboard |
The formula explained
inverse: divide to convert back
SI base: all conversions go through the SI base unit
This tool runs entirely in your browser. No data is sent to any server. Furthermore, all processing happens locally using JavaScript.
Example usage
Enter a typical value or paste sample input to see how the Fuel Efficiency Converter works.
Furthermore, the output shows the result with a clear explanation of the conversion or calculation.
About Fuel Efficiency Converter
Fuel efficiency is inverse: L/100km decreases as efficiency improves; MPG increases. L/100km = 235.215 / US MPG. UK MPG uses the imperial gallon (4.546 L) vs US gallon (3.785 L), so UK MPG is always higher than US MPG for the same fuel consumption. Furthermore, electric vehicle efficiency is measured in kWh/100km or MPGe.
What is a Fuel Efficiency Converter?
Typical fuel consumption: small car 5-7 L/100km (40-47 MPG), SUV 8-12 L/100km (20-29 MPG), heavy truck 25-40 L/100km. Electric vehicle: 15-20 kWh/100km. Furthermore, 1 L of petrol has ~8.9 kWh energy; EV uses this ~4× more efficiently.
The Fuel Efficiency Converter is a free browser-based tool available on LazyTools. Furthermore, it requires no installation and works on any device with a modern browser.
Why use this tool
This tool saves time on repetitive fuel efficiency converter tasks. Furthermore, browser-based processing keeps your data private.
Moreover, consistent results eliminate manual calculation errors and improve workflow efficiency.
Common mistakes
Always verify the output for critical applications. Furthermore, browser-based tools rely on JavaScript — results may vary slightly between browsers.
Copy the output before closing the tab, as browser tools do not save state between sessions. Moreover, bookmark the tool for easy access.
Tips for best results
Use keyboard shortcuts for faster workflow. Ctrl+A selects all output text for quick copying. Furthermore, most tools update output in real time as you type.
For best results, use a modern browser (Chrome, Firefox, Edge). Moreover, if a tool does not load correctly, try refreshing the page.
Frequently asked questions
US MPG = 235.215 / L/100km. For 6 L/100km: 235.215/6 = 39.2 US MPG. Furthermore, UK MPG = 282.48 / L/100km.
<6 L/100km (>39 US MPG) is good. <4 L/100km is excellent (hybrids/efficient diesels). Furthermore, petrol and diesel efficiencies differ slightly.
UK gallon = 4.546 L vs US gallon = 3.785 L. Same car: ~20% higher UK MPG. Furthermore, a car rated 30 US MPG ≈ 36 UK MPG.
Miles Per Gallon equivalent — compares EV efficiency to petrol. 1 gallon petrol energy ≈ 33.7 kWh. Furthermore, EPA rates most EVs at 100-130 MPGe.
Cost = distance × L/100km / 100 × fuel price. For 500 km at 7 L/100km × £1.50/L = 500 × 7/100 × 1.50 = £52.50. Furthermore, check the fuel cost calculator for detailed journey cost.
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