Fuel Economy Calculator
Last updated: 2026-06-25
Fuel economy (km/L) = distance ÷ fuel added. For example, if you drove 480 km on 40 L, then 480 ÷ 40 = 12 km/L is your real-world economy.
Enter a fuel price and the cost per km (= fuel price ÷ fuel economy) is calculated too. Real-world economy is usually lower than the rated figure.
Enter Trip and Fuel Details
Real-world fuel economy
0 km/L
| Item | Value |
|---|---|
| Distance driven | |
| Fuel added | |
| Real-world fuel economy | |
| Cost per km |
This is an estimate for reference. An average over several segments is more accurate than a single measurement, and economy varies with driving habits, roads, and weather.
How to Use
- Enter the distance — enter the distance driven (km) between one refuel and the next.
- Enter the fuel added — enter the fuel added (L) over that segment.
- Check the result — press Calculate to see your real-world fuel economy (km/L), plus cost per km if you enter a fuel price.
How Fuel Economy and Cost per km Work
Fuel economy is the distance you can travel per unit of fuel, with the formula fuel economy (km/L) = distance ÷ fuel added. The higher the value, the better the efficiency. Applying a fuel price gives cost per km = fuel price ÷ fuel economy, the money it takes to drive 1 km.
| Real-world economy | Cost per km | Cost per 100 km |
|---|---|---|
| 8 km/L | 213 won | 21,250 won |
| 12 km/L | 142 won | 14,167 won |
| 16 km/L | 106 won | 10,625 won |
| 20 km/L | 85 won | 8,500 won |
The most accurate way to measure real-world economy is the "full-to-full" method. Fill the tank, reset the trip meter to 0, and calculate using the distance and fuel added the next time you fill up completely. Put that real-world economy into the fuel cost calculator to estimate your commuting fuel cost more accurately.
Frequently Asked Questions (FAQ)
How is fuel economy calculated?
Fuel economy (km/L) = distance ÷ fuel added. For example, if you drove 480 km on 40 L, then 480 ÷ 40 = 12 km/L is your real-world fuel economy.
How do I measure real-world fuel economy accurately?
Fill the tank, reset the trip meter to 0, then calculate using the distance driven and fuel added the next time you fill up completely. This is called the 'full-to-full' method.
How is cost per km calculated?
Cost per km = fuel price (won/L) ÷ fuel economy (km/L). For example, at 12 km/L and 1,700 won/L, that's 1,700 ÷ 12 = about 142 won/km.
Why do rated and real-world fuel economy differ?
The official (combined) economy in the catalog is measured under standard test conditions. In reality, hard acceleration/braking, city congestion, air conditioning/heating, load weight, and tire pressure change your real-world economy, which is usually lower than the rated figure.
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Last updated: 2026-06-25