Fuel Economy Converter

Fuel Economy Converter - MPG, L/100km, km/L | Tuttilo

Convert fuel economy and efficiency units between different measurement systems.

Choose your starting fuel economy unit: liters per 100 kilometers, kilometers per liter, miles per gallon (US), or miles per gallon (Imperial). Enter your vehicle's fuel economy figure. Select the unit you want to convert to. Tuttilo calculates the conversion instantly, accounting for the inverse relationship between distance-per-fuel and fuel-per-distance metrics. Note that US and Imperial gallons differ, affecting MPG values. The tool processes everything in your browser, keeping your vehicle data private.

Travelers renting cars abroad convert fuel economy specifications to their familiar units for comparison shopping. Car buyers evaluate vehicles with efficiency ratings in different systems to find the most economical option. Fleet managers track vehicle efficiency across international operations where different regions report using different standards. Environmental advocates calculate and compare carbon footprints when efficiency data uses various measurement systems. Automotive journalists convert manufacturer specifications to their audience's preferred units for reviews.

Lower L/100km values indicate better efficiency (inverse metric) while higher MPG values indicate better efficiency (direct metric), which can cause confusion when comparing. US MPG is approximately 17% lower than Imperial MPG for the same vehicle because US gallons are smaller. Real-world fuel economy typically runs 15-25% worse than official ratings due to testing methodology limitations—account for this when budgeting fuel costs. Hybrid vehicles often show dramatically better city MPG than highway MPG (opposite of traditional vehicles) due to regenerative braking benefits in stop-and-go traffic.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.