Everyday Utilities
Rates & guidance reviewed
Fuel is one of the easiest trip costs to underestimate. Whether you are planning a motorway run, comparing MPG cars, or working out a week of commuting, a clear cost-per-mile figure helps you budget in pounds and pence.
This free UK fuel cost calculator uses miles, UK (imperial) MPG or L/100km, and the pump price per litre. Set multiple trips for a return journey or a working week. Everything runs in your browser — no account and no data stored.
Real economy depends on speed, traffic, weather and load. Treat results as planning estimates, not a guarantee of what the tank will cost.
Prefer the written walkthrough? Start with How UK car tax (VED) works in 2026/27, How UK fuel cost is calculated from miles, MPG and the pump price or How UK VAT is calculated: add, remove and the 1.20 trap. Guides match the figures on this page.
UK fuel · miles, MPG (imperial) or L/100km, £ per litre
One-way trip length in miles
UK miles per imperial gallon (common on UK dashboards)
e.g. 1.45 for 145p/L
Use 2 for a return journey, or 10 for a working week
Estimates only. Real economy varies with speed, load, weather and traffic. Does not include parking, congestion charge, insurance or wear and tear.
Static sample calculations you can read without using the form. Figures match this tool's maths — always re-run with your own numbers for a personal estimate.
Default trip using UK imperial MPG and a typical pump price.
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Litres = (100 ÷ 45) × 4.54609. Same figures as the written fuel-cost guide.
Longer run using the metric economy figure.
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Five working days, there and back.
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Same distance and pump price — only economy changes.
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The gap between 35 and 50 mpg on this trip is £5.65 — larger than raising the pump from £1.45 to £1.60 at 45 mpg (£1.51 extra).
Many UK cars still show miles per gallon on the trip computer. That figure uses the imperial gallon (about 4.55 litres), not the US gallon. Official WLTP figures are often quoted in L/100km — lower is more efficient. This tool supports both so you can use whichever number you have.
Cost per mile is useful for splitting fuel with passengers or comparing a petrol car to public transport. For company mileage, HMRC has separate approved mileage allowance payments (AMAPs) that are not the same as your actual pump cost.
With UK MPG: litres ≈ (miles ÷ MPG) × 4.54609, then multiply by £ per litre. With L/100km: convert miles to kilometres, then litres = (L/100km ÷ 100) × km. Multiplying by the number of trips scales both fuel and cost. A longer walk-through of this model, the £14.65 default, commute scaling, Fuel Duty / VAT inside the pump price, and why 55p a mile is not your fuel cost is in the written fuel-cost guide.
Always confirm rates, bands and eligibility on official pages. Our tools are simplified estimators for guidance only.