Fuel Efficiency Converter

What is the Fuel Efficiency Converter?

A fuel efficiency converter translates between the different systems used to measure how far a vehicle travels on a given amount of fuel — miles per gallon (MPG), liters per 100 kilometers (L/100km), and kilometers per liter (km/L). The US uses MPG, most of Europe and Asia use L/100km, and some regions use km/L. When you're comparing car specs across markets, estimating road trip costs, or just trying to understand a foreign car review, this converter gives you the number in whatever unit makes sense to you.

How Does It Work?

Fuel efficiency units don't convert with a simple multiplication — some require inversion because they measure the same thing from opposite directions (distance per fuel vs fuel per distance).

Key conversions:

MPG (US) to L/100km: 235.215 ÷ MPG

L/100km to MPG (US): 235.215 ÷ L/100km

MPG to km/L: MPG × 0.4251

km/L to L/100km: 100 ÷ km/L

Input: your vehicle's fuel efficiency figure

Conversion Factor: depends on the unit pair

How to Use CalciHub's Fuel Efficiency Converter

1. Enter your vehicle's fuel efficiency number.

2. Select the unit whose number is in MPG, L/100km, or km/L.

3. Choose the unit you want to convert to.

4. The result appears immediately.

Tip: A lower L/100km number is better (using less fuel per distance), while a higher MPG number is better. Don't confuse the direction — this is where most conversion mistakes happen.

A Quick Example

A traveler is renting a car in Europe. The car specs list fuel consumption as 6.5 L/100km. They want to understand this in MPG since that's what they're familiar with from home.

Input: 6.5 L/100km

Converting to: MPG (US)

235.215 ÷ 6.5 = 36.19 MPG

Output: approximately 36.2 MPG

That's a reasonably efficient car by most standards. Knowing the MPG equivalent helps the traveller estimate fuel costs for the trip using pumping rates they understand.

Frequently Asked Questions