Fuel calculator
Petrol Consumption Calculator UK
Estimate fuel required for a journey.
Estimate petrol required
What your result means
This estimates the petrol required for the journey distance and UK MPG entered. Kilometres are converted to miles first, and selecting return journey doubles the distance before fuel use is calculated.
Worked example
Using a 250-mile journey and 45 UK MPG:
- UK gallons used
- 5.56
- Petrol required
- 25.3 litres
A return journey with the same MPG doubles the estimated litres required.
Formula
Petrol required for 250 miles
| UK MPG | Estimated litres |
|---|---|
| 30 | 37.9 litres |
| 40 | 28.4 litres |
| 50 | 22.7 litres |
| 60 | 18.9 litres |
Helpful questions
How do I calculate petrol consumption for a journey?
Divide journey miles by UK MPG to find UK gallons, then multiply by 4.54609 for litres. The Petrol Calculator can also estimate journey fuel cost.
Can I enter kilometres?
Yes. The calculator converts kilometres to miles before applying the UK MPG calculation.
How does a return journey affect fuel required?
It doubles the entered distance. With unchanged MPG, the estimated litres also double.
Why can actual fuel consumption differ?
Traffic, speed, driving style, load and weather affect real MPG. Use measured MPG where available.
Related calculators
- Petrol Calculator
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- Full Tank Cost Calculator
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- MPG Calculator
Calculate your real-world UK fuel economy.