How to Use the Fuel Economy & Mileage Converter
This calculator is designed to provide immediate answers without manual arithmetic or confusing steps. Simply input your values into the fields above; results update automatically as you adjust numbers. You can also customize your currency and tax preferences using the region selector in the header.
Formula & Calculation Method
US MPG = 235.215 ÷ (L/100km); km/L = 100 ÷ (L/100km); UK MPG = 1.20095 × US MPG
Our algorithms strictly follow standard international accounting, scientific, and engineering formulas to ensure 100% precision.
Frequently Asked Questions
Why does lower L/100km mean better efficiency?
Liters per 100km measures consumption (how much fuel used for a set distance), so lower is better. MPG measures distance (miles covered per unit of fuel), so higher is better.
What is the difference between US MPG and UK MPG?
A UK Imperial gallon (4.546 liters) is ~20% larger than a US liquid gallon (3.785 liters), so UK MPG values are numerically ~20% higher for the same car.