Fuel Economy Unit Converter
Effortlessly switch between MPG (US/UK), km/L, and L/100 km. Instant, accurate gas mileage and fuel consumption conversions.
Fast, Free, Private Fuel Economy Converter (Offline)
Convert MPG (US/UK), km/L, and L/100 km instantly. 100% client side, lifetime free, unlimited use. No uploads, no sign ups, truly private.
Top, fast, best-in-class, and unlimited. Your information is 100% confidential and secure.
Why people love this fuel economy converter
Offline & secure
Runs entirely in your browser. Your values never leave your device.
Unlimited & free forever
No accounts, no limits convert as much as you want.
Fast & simple
Pick units, type a value, get results instantly with clear precision.
Works everywhere
Modern browsers on Windows, Mac, Linux, and mobile devices.
No data collected
100% client-side processing keeps your data private.
Accurate results
Reliable conversion factors (US vs UK gallons) with smart rounding.
Popular uses worldwide
Drivers & car shoppers
Compare MPG (US/UK), L/100 km, and km/L for better fuel choices.
Fleet & logistics
Standardize mixed-unit reports across regions and vehicles.
Auto reviewers & researchers
Publish consistent numbers in both imperial and metric markets.
Import/export
Convert US MPG to L/100 km for EU listings and vice versa.
Education
Learn the relationships among MPG, km/L, and L/100 km.
EV context
Explain gas-mileage equivalents when comparing ICE vs EV efficiency.
How to convert fuel economy units
- Select your “From” unit (e.g., L/100 km).
- Enter a value (e.g., 6.5).
- Select your “To” unit (e.g., MPG US or MPG UK).
- See instant results and the 1 unit summary below.
- Use “Reset” to start again.
Tip: Change either side both fields update intelligently.
Supported units
Formulas and constants
- 1 mpg (US) = 0.4251437075 km/L
- 1 mpg (UK/Imp) = 0.354006 km/L
- L/100 km = 100 ÷ (km/L)
- MPG (US) = 235.214583 ÷ L/100 km
- MPG (UK) = 282.480936 ÷ L/100 km
- MPG (UK) ≈ MPG (US) × 1.20095
Best practices
- Pick the correct gallon type: US vs UK/Imperial.
- When comparing international specs, convert to a single unit first.
- Round only at the end if you’ll do further calculations.
- Keep original values for auditing and records.
Frequently Asked Questions
Is it private and secure?
Yes. Everything runs locally in your browser no uploads, no tracking, no servers.
Is it really free and unlimited?
Yes. Lifetime free, unlimited conversions, and no sign ups.
Which units are supported?
MPG (US), MPG (UK/Imperial), km/L, and L/100 km.
Does it work offline?
Yes. Your browser caches assets after the first visit and can run offline.
How accurate are results?
We use precise conversion constants (US vs UK gallons) and smart rounding for readability.
Can I use it on mobile?
Absolutely. It works on modern mobile and desktop browsers.
Global availability (GEO)
Built for users worldwide: USA, UK, Canada, Australia, India, EU (Germany, France, Spain, Italy, Netherlands), Middle East (UAE, Saudi Arabia), Asia (Singapore, Malaysia, Philippines, Indonesia, Japan, South Korea), Africa (Nigeria, South Africa, Egypt), and Latin America (Brazil, Mexico, Argentina).
Also searched as: Fuel economy converter, MPG to L/100 km, L/100 km to MPG, km/L to MPG, gas mileage calculator, fuel consumption converter, US MPG vs UK MPG, liters per 100 km converter.
Multilingual: conversor de consumo de combustible / mpg a L/100 km (ES), convertisseur de consommation de carburant (FR), Kraftstoffverbrauch umrechnen / L/100 km in mpg (DE), convertitore consumo carburante (IT), conversor de consumo de combustível (PT), конвертер расхода топлива (RU), 燃費換算 / MPG から L/100km (JA), 油耗换算 (ZH), 연비 변환기 (KO).
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