L/100 km means litres of fuel used to drive 100 kilometres. It is the standard way many Canadian vehicle ratings describe fuel consumption. Lower numbers are better because the vehicle uses less fuel to travel the same distance.
If you are used to miles per gallon, L/100 km can feel backwards at first. With MPG, a bigger number is better. With L/100 km, a smaller number is better.
How to read the number
A car rated at 7.0 L/100 km uses about 7 litres of fuel for every 100 kilometres in the rated test scenario. A vehicle rated at 10.0 L/100 km uses more fuel, so it will generally cost more to drive the same annual distance.
The number is a rate, not a fixed fuel bill. Your actual cost depends on how far you drive and what you pay per litre. The same 8.0 L/100 km car costs much more to operate at 30,000 km per year than at 10,000 km per year.
City, highway, and combined
Ratings are often shown separately for city and highway driving. The combined number blends both, but your real cost depends on your own driving mix. More city driving can make efficient hybrids look better.
- City rating: estimates fuel use in lower-speed, stop-and-go conditions.
- Highway rating: estimates fuel use at steadier road speeds.
- Combined rating: blends city and highway driving into one easy comparison number.
The combined rating is useful for quick shopping, but it may not match your life. A downtown commuter and a highway commuter can see different costs from the same vehicle.
How to estimate annual fuel use
You can estimate yearly litres with this formula:
If you drive 20,000 km per year in a vehicle rated at 8.0 L/100 km, the estimate is:
Then multiply litres per year by fuel price. At $1.70 per litre, 1,600 litres costs about $2,720 per year.
Comparing two ratings
Small L/100 km differences can become meaningful over time. A vehicle rated at 7.0 L/100 km uses about 1,400 litres over 20,000 km. A vehicle rated at 9.0 L/100 km uses about 1,800 litres over the same distance. That is a 400 litre difference each year.
At $1.70 per litre, that difference is about $680 per year. Over five years, assuming the same distance and fuel price, that becomes about $3,400.
Why real-world fuel use can differ
Official ratings are useful for comparing vehicles on the same basis, but your actual fuel use can be higher or lower. Weather, tires, traffic, speed, cargo, roof racks, short trips, maintenance, and driving style all affect fuel consumption.
Cold weather can be especially noticeable in Canada. Engines take longer to warm up, winter tires add rolling resistance, and short trips may happen before the vehicle reaches its most efficient operating temperature.
L/100 km versus cost
The lowest L/100 km rating does not always mean the cheapest vehicle to own. Purchase price, insurance, financing, maintenance, depreciation, and incentives can matter more than fuel in some comparisons. But fuel ratings are still one of the easiest costs to estimate before buying.
How to use the calculator
- Choose the vehicles you want to compare.
- Set your annual kilometres.
- Enter a realistic gas price per litre.
- Adjust the city/highway split to match your driving.
- Compare the yearly fuel cost and long-term difference.
Bottom line
L/100 km tells you how much fuel a vehicle uses to travel 100 kilometres. Lower is better. Once you know the rating, your annual distance, and the fuel price, you can turn that rating into a practical yearly cost estimate.