PetrolCalculator

Fuel calculator

How Much Petrol for 100 Miles?

Estimate petrol needed for 100 miles or an editable journey.

Estimate petrol required

Enter your MPG to estimate petrol required for 100 miles.

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 miles, 45 UK MPG and 142p per litre:

Journey miles
100
UK gallons required
2.22
Petrol required
10.1 litres
Estimated fuel cost
£14.35

The same model also applies an optional return journey before calculating fuel use.

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

Petrol required for 100 miles

UK MPGLitres required
3015.2 litres
4011.4 litres
509.1 litres
607.6 litres

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.

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