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Running Costs

Journey Fuel Cost Calculator

What will this drive actually cost in fuel? Enter the distance, your car's MPG and the pump price for the trip cost, fuel used and cost per mile, plus annual commute cost, a per-person split and a comparison with another car.

Optional: commute, sharing & comparison

Enter your trip to see the cost

Estimates only, based on the figures you enter and steady real-world economy. Actual MPG varies with speed, load, traffic, terrain and weather, and pump prices change frequently. Tolls, parking and non-fuel running costs are not included. For the most accurate result use your own car's trip-computer average. Not financial advice.

How journey fuel cost is worked out

Three numbers decide it: how far you go, how far your car travels per gallon, and what fuel costs. The method is:

So 100 miles at 45 mpg uses about 10.1 litres; at 145p that's roughly £14.65. Tick return journey to double the distance there and back.

Fuel cost per mile

A useful shortcut is cost per mile = pump price (p/litre) × 4.546 ÷ MPG. It doesn't depend on distance, so it's the cleanest way to compare two cars or sanity-check any trip. At 145p and 45 mpg that's about 14.6p a mile.

What a regular trip really costs

Commutes add up fast. Enter how many times a week you make the trip and the calculator shows the weekly, monthly and yearly fuel bill, often a bigger number than people expect, and a strong argument for a more efficient car, car-sharing or combining journeys.

Cutting the cost

The biggest lever is MPG: smoother driving, steady motorway speeds, correct tyre pressures, less weight and less idling all help. Sharing the trip splits the cost directly, so use the people sharing field to see the per-person figure.

Frequently asked questions

How do I calculate a journey's fuel cost?

Distance ÷ MPG gives gallons; × 4.546 gives litres; × pump price gives the cost. 100 miles at 45 mpg and 145p is about £14.65.

How do I work out cost per mile?

Pump price (p/litre) × 4.546 ÷ MPG. At 145p and 45 mpg that's roughly 14.6p per mile, regardless of distance.

Does a return trip just double it?

Yes, the return option doubles the distance, so the fuel used and the cost double too (assuming similar economy each way).

How much is my commute per year?

Cost of one commute × trips per week × 52. The optional fields work this out for you, with weekly and monthly figures too.