How many litres of petrol does it take to travel 100km?

Litres of petrol per 100km: 6L vs 20L consumption

Understanding the litres of petrol per 100km required for travel helps drivers identify significant efficiency gaps between different vehicle classes. Factors like vehicle weight, aerodynamic drag at high speeds, and driving habits determine how much fuel remains in the tank. Learn which variables influence fuel economy to lower expenses and improve overall vehicle performance during long journeys.

How Many Litres of Petrol to Travel 100km?

For a typical modern passenger car, it takes between 6 and 12 litres of petrol to travel 100km.^[1] However, this range is highly dependent on vehicle size, engine efficiency, and the driving environment. Small, aerodynamic hatchbacks often consume as little as 4.5 to 6 litres per 100km, while large SUVs or heavy performance trucks can easily exceed 15 to 20 litres in stop-and-go city traffic.

Understanding this metric, known as L/100km, is the global standard for measuring fuel efficiency. Unlike the US system of Miles Per Gallon (MPG), where a higher number is better, with L/100km, a lower number indicates a more efficient vehicle. But heres the thing that most drivers miss: even a small increase in speed or a slight drop in tire pressure can drastically change these numbers. Ill reveal the single biggest factor that ruins fuel economy in the driving habits section below.

Average Fuel Consumption by Vehicle Class

Vehicle weight and aerodynamics are the primary physical constraints on fuel usage. Industry benchmarks indicate that for every 100kg of additional weight, fuel consumption typically increases by about 2% to 3%.^[2] This explains why a compact car and a full-sized SUV with the same engine technology will have vastly different efficiency ratings.

In my experience testing different rentals for long-distance trips, Ive found that mid-sized sedans usually hit a sweet spot. They provide enough power for highway merging while maintaining a steady 7.5 litres per 100km. I once tried to save money by renting a smaller car for a mountainous route, but the tiny engine had to work so hard on the inclines that I ended up using more petrol than a larger V6 would have. It was a frustrating lesson in matching the tool to the task.

Current data for 2026 models shows significant efficiency gains across the board: Compact/City Cars: Typically range from 4.8 to 6.2 L/100km. Mid-sized Sedans: Usually average between 6.5 and 8.5 L/100km. Small to Medium SUVs: Often consume between 7.5 and 10.5 L/100km. Large SUVs and Pickups: Generally range from 11.5 to 18.0 L/100km.

City vs. Highway: Why Driving Conditions Matter

A cars petrol consumption isnt a static number. Its a dynamic variable. City driving is significantly less efficient because of idling and the energy required to repeatedly move a stationary mass. In urban environments, a car might use 30% to 50% more fuel than it does on a flat highway at a constant speed.

Modern stop-start technology has mitigated some of this, but it doesnt change physics. Ive spent hours - hours Ill never get back - idling in downtown traffic watching my digital fuel gauge climb from a respectable 8.0 L/100km to a depressing 14.0 L/100km. Its a helpless feeling. Most manufacturers provide two ratings for this reason: Urban and Extra-Urban (highway). Always look at the combined rating for the most realistic expectation.

The Impact of Speed on Consumption

Aerodynamic drag increases with the square of speed. This means that driving at 120km/h requires significantly more fuel than driving at 100km/h. Specifically, increasing your speed from 100km/h to 120km/h can increase fuel consumption by as much as 20% for some vehicles. Its^[3] the difference between arriving 10 minutes earlier and spending an extra $15 at the pump.

Is 10 Litres Per 100km Good?

Whether 10 L/100km is good depends entirely on what you are driving. For a large 4x4 or a performance sports car, 10 litres is exceptionally efficient. However, for a modern compact car, 10 L/100km would be considered quite poor - well, not just poor, but potentially a sign of a mechanical issue or extremely aggressive driving habits.

Remember the critical factor I mentioned earlier that ruins fuel economy? Its jackrabbit starting. Rapid acceleration from a stoplight can use up to 40% more fuel compared to a gradual, smooth increase in speed. ^[4] By treating the gas pedal like an eggshell, you can often drop your average consumption by 1.5 to 2 litres without changing your car or your route. It takes patience, but the savings add up over thousands of kilometres.

Fuel Consumption Comparison: ICE vs. Hybrid vs. Diesel

Standard Petrol (ICE)

1. 7.0 to 9.5 (Combined)
2. Infrequent drivers or those with low annual mileage
3. Lower initial purchase price and simpler maintenance

⭐ Hybrid Petrol-Electric

1. 3.8 to 5.5 (Combined)
2. City commuters and high-traffic urban areas
3. Regenerative braking saves up to 35% fuel in stop-go traffic

Turbo Diesel

1. 5.5 to 7.0 (Combined)
2. Long-distance highway driving and heavy towing
3. Superior torque and 20-30% better highway efficiency than petrol

Hùng's Commute: From District 7 to District 1

Hùng, a 32-year-old office worker in Ho Chi Minh City, noticed his mid-sized sedan was consuming 12 L/100km during his daily 10km commute. He was frustrated by the rising fuel costs and the constant stop-and-go traffic that turned a 20-minute drive into an hour.

First attempt: He tried using 'Premium' high-octane petrol, thinking it would burn more efficiently. Result: He spent more money per litre but saw zero improvement in his L/100km average, as his engine wasn't tuned to benefit from higher octane.

He realized the problem wasn't the fuel, but his 'aggressive' response to traffic gaps. He began using his car's 'Eco Mode' and focused on coasting toward red lights rather than braking at the last second.

After 4 weeks, Hùng's consumption dropped to 9.5 L/100km - a 21% improvement. He saved roughly 600.000 VND per month and reported feeling significantly less stressed during his commute.