How to estimate fuel cost per drive, and cut it

Knowing what a trip costs changes how you think about it. Here is a quick way to estimate it.

The basic formula

Fuel cost = distance × fuel used per distance × price per unit of fuel.

For example, if your car uses 8 litres per 100 km, a 25 km drive uses about 2 litres. At a price of 1.50 per litre, that is around 3.00.

Where to get your numbers

• Fuel use: check your car’s trip computer, or fill the tank, drive, and refill to see how much you used.
• Price: use what you actually paid at your last fill-up.
• Distance: Road Rank measures this for each drive.

Let the app help

In Road Rank you can add your vehicle to see an estimated fuel cost per drive. It is an estimate, because real consumption varies with traffic, load and driving style.

Ways to reduce the cost

1. Accelerate gently. Hard pull-aways burn more fuel.
2. Anticipate and coast. Let the car slow naturally rather than braking late.
3. Keep a steady speed. Constant speeds are more efficient than speeding up and slowing down.
4. Check tyre pressure. Under-inflated tyres increase resistance.
5. Remove extra weight and roof racks.
6. Combine short trips. A warm engine is more efficient.

Compare trips

Look at similar journeys on different days. If the calm ones cost less, your habits are working.

Be realistic

Savings depend on your car, roads and traffic. Treat any promise of a fixed percentage with caution.