Real Mileage Checker – UK
Measure actual fuel efficiency using distance travelled and fuel filled. Free, no sign-in and no paid maps API required.
Check your real fuel mileage
How this calculator works
On UK fuel receipts you pay per litre while the familiar fuel-economy figure is miles per Imperial gallon. Enter miles driven and litres purchased: the checker converts the litres to Imperial gallons using 4.54609 litres per gallon, then calculates UK mpg. It also reports spending in pounds and cost per mile. Do not put a US mpg rating or pence-per-litre figure into these measured inputs.
For more planning tools, visit the UK fuel cost calculator or Trip Cost Splitter.
A worked real-mileage example for United Kingdom
A journey of 300 miles using 30 litres gives approximately 45.46 Imperial mpg. At an illustrative £1.55 per litre, fuel spending is £46.50, or about £0.16 per mile. These figures are arithmetic examples, not current pump prices.
Use the right local units
UK fuel pumps dispense litres, while mpg means miles per Imperial gallon. One Imperial gallon is approximately 4.54609 litres. Never mix a US mpg figure with an Imperial mpg input; the resulting costs would be misleading.
Practical tips for reliable results
Use the same fill level at the beginning and end of a UK mileage check and keep the till receipt with its litre quantity, not just its total in pounds. Record the trip odometer in miles and include any partial refills between the two full tanks. A motorway run and a week of short urban journeys are different conditions; compare like with like before treating a variation in Imperial mpg as a mechanical issue.
Convert a UK refill into Imperial mpg
If a UK vehicle travels 300 miles between comparable full-tank fills and takes 30 litres to refill, it has used about 6.60 Imperial gallons. That works out to approximately 45.46 UK mpg. The result is not the same as US mpg: a UK Imperial gallon contains about 4.54609 litres, versus about 3.78541 litres in a US gallon. Matching the gallon definition matters whenever you compare published figures.
Because UK pumps charge by the litre, keep the actual litre quantity and receipt total when recording refills. Try comparing similar kinds of driving—urban journeys with urban journeys, motorway travel with motorway travel—rather than treating one unusual tank as a permanent change in your vehicle's efficiency.
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