PetrolCalculator

Fuel calculator

How Much Petrol for 100 km?

Estimate petrol needed for 100 km or an editable journey.

Estimate petrol required

Enter your MPG to estimate petrol required for 100 km.

What your result means

This estimates petrol required from journey distance and UK MPG. The result is an estimate: real-world fuel use can change with traffic, speed, load and weather.

Worked example

Using 100 km, converted through the exact kilometre-to-mile constant, and 45 UK MPG:

Journey miles
62.14
UK gallons required
1.38
Petrol required
6.3 litres

Kilometres are converted to miles before applying UK MPG.

Formula

UK gallons=Journey milesUK MPG\text{UK gallons}=\frac{\text{Journey miles}}{\text{UK MPG}}
Litres=UK gallons×4.54609\text{Litres}=\text{UK gallons}\times4.54609

Helpful questions

Does a return journey double the estimate?

Yes. With the same MPG and price, selecting a return journey doubles the entered distance, fuel required and estimated fuel cost.

Why can actual fuel use differ?

Traffic, speed, driving style, load, weather and road conditions affect real-world MPG. Use the MPG Calculator to measure a real figure.

Does this use UK or US MPG?

It uses UK / imperial MPG and converts kilometres to miles before applying the UK-gallon calculation. Convert US MPG to UK MPG if needed.

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