Enter distance traveled and fuel consumed to calculate km per liter. The tool also shows L/100km and converts fuel economy to mpg (US), mpg (UK), km/gal (US), mi/L, and gal/100mi.
Formulas & Conversions
Kilometers per Liter (km/L) = Distance (km) ÷ Fuel Consumed (L)
Consumption Formula:
Liters per 100km = (Fuel Consumed (L) ÷ Distance (km)) × 100
Standard Conversions Used:
1 mile = 1.609344 kilometers
1 US Gallon = 3.78541 liters
1 UK (Imperial) Gallon = 4.54609 liters
Getting a clear picture of your vehicle’s performance relies on calculating its actual fuel usage. The km per liter calculator helps you figure out your car’s fuel economy and overall volume consumption. By entering your distance traveled and the fuel you used, you get immediate results in km/L, L/100km, and several other standard global units including miles per gallon (MPG), km/gal (US), mi/L, gal(US)/100mi, and gal(UK)/100mi.
What Is Kilometers Per Liter (km/L)?
Kilometers per liter (km/L) is a standard metric used to measure fuel economy. It defines how many kilometers your vehicle travels using a single liter of fuel. A higher km/L number indicates higher efficiency because the vehicle covers more distance per volume of fuel.
While km/L measures efficiency (distance per volume), the calculator also outputs your “fuel consumption,” which is typically measured in Liters per 100km (L/100km). This metric shows volume per distance. A lower L/100km number indicates a more efficient vehicle, as it requires less fuel to travel a standard 100-kilometer distance.
Why Calculate Your Fuel Economy?
Tracking your vehicle’s fuel economy establishes a clear baseline for its performance. Recording your km/L or L/100km over time allows you to see how different driving conditions, speeds, or specific routes alter the volume of fuel your car requires. It provides a calculated, numerical value for efficiency rather than relying on an estimate from the dashboard fuel gauge.
Fuel Economy and Consumption Formulas
This calculator runs straightforward mathematics to evaluate efficiency. The tool accepts raw inputs and processes them using these primary formulas:
Primary Fuel Economy Formula:$$\text{Kilometers per Liter (km/L)} = \frac{\text{Distance (km)}}{\text{Fuel Consumed (L)}}$$
Primary Fuel Consumption Formula:$$\text{Liters per 100km} = \left( \frac{\text{Fuel Consumed (L)}}{\text{Distance (km)}} \right) \times 100$$
When you select non-metric units like miles or gallons, the tool applies standard conversion constants before evaluating the main formulas:
- $$1 \text{ mile} = 1.609344 \text{ kilometers}$$
- $$1 \text{ US Gallon} = 3.78541 \text{ liters}$$
- $$1 \text{ UK Gallon} = 4.54609 \text{ liters}$$
Real-World Example: Calculating Fuel Efficiency
Suppose you have recorded a trip distance of 500 kilometers on your odometer, and your receipt shows you bought 35 liters of fuel. You now have the relevant information needed for the calculator.
Go to the Distance Traveled box and enter 500. Ensure the unit dropdown next to it is set to “km”. Next, hit the tab key or click into the Fuel Consumed box and enter 35. Ensure the unit is set to “Liters”.
The numbers calculate immediately as you type. Your Fuel Economy (Efficiency) is calculated as 14.29 km/L. In the lower box, your Fuel Consumption (Volume per Distance) is calculated as 7.00 L/100km.
To convert these metrics, click the unit dropdown next to the Fuel Economy result and select “mpg (US)”. The calculator instantly changes the result to 33.60 mpg (US). You can similarly click the unit dropdown next to the Fuel Consumption result and select “gal(US)/100mi” to see that your vehicle consumed 2.98 gallons per 100 miles.
Fuel Efficiency Conversion Table
Different regions use different base units to measure fuel efficiency and consumption. This table illustrates how standard metric baseline calculations convert into common US and UK equivalents.
| Kilometers per Liter (km/L) | Liters per 100km (L/100km) | Miles per Gallon (US MPG) | Miles per Gallon (UK MPG) |
|---|---|---|---|
| 8.00 km/L | 12.50 L/100km | 18.82 mpg | 22.60 mpg |
| 10.00 km/L | 10.00 L/100km | 23.52 mpg | 28.25 mpg |
| 12.00 km/L | 8.33 L/100km | 28.23 mpg | 33.90 mpg |
| 15.00 km/L | 6.67 L/100km | 35.28 mpg | 42.37 mpg |
| 20.00 km/L | 5.00 L/100km | 47.04 mpg | 56.50 mpg |
| 25.00 km/L | 4.00 L/100km | 58.80 mpg | 70.62 mpg |
Frequently Asked Questions
What is the difference between Fuel Economy and Fuel Consumption in the results?
The calculator generates two distinct results because they measure performance differently. Fuel Economy measures distance divided by volume (how far you go on a set amount of fuel, like km/L). Fuel Consumption measures volume divided by distance (how much fuel it takes to cover a set distance, like L/100km).
How do I manually convert km/L to L/100km?
To convert kilometers per liter to liters per 100 kilometers manually, simply divide 100 by your calculated km/L figure. For example, if your car gets 20 km/L, the math is $100 \div 20 = 5$. The consumption is 5 L/100km.
Why does the calculator include both US and UK gallons?
The US gallon and the UK (Imperial) gallon hold different volumes. A US gallon equals approximately 3.785 liters, while a UK gallon is larger, holding roughly 4.546 liters. Selecting the incorrect gallon measurement for your region will cause the calculator’s baseline conversion to produce an inaccurate final result.
Can I calculate my MPG using kilometers and liters?
Yes, the calculator processes cross-unit inputs directly. You can input your distance in kilometers and your fuel in liters. You can then change the output units from km/L to either mpg (US) or mpg (UK). The calculator also supports outputting consumption as gal(US)/100mi or gal(UK)/100mi based on those metric inputs.
What happens if I enter my distance in miles?
If you select miles as your input unit, the tool applies a multiplier of 1.609344 to convert the miles into kilometers in the background. It then runs the standard metric calculations to find your base economy and consumption before converting the final outputs into whichever units you have selected in the result dropdowns.
Does the tool support inverted metric units?
Yes, if you need to calculate miles per liter or kilometers per gallon, those options are available. Under the Fuel Economy output dropdown, you can select “mi/L” to see how many miles you can drive per liter, or select “km/gal (US)” to measure metric distance against US liquid volume.
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