BortioTMWhy full-to-full is the useful method
A dashboard estimate can move with traffic, temperature and the last few kilometres. A full-to-full calculation uses what crossed the pump and the distance recorded between two comparable points. Fill the tank, reset the trip meter, drive normally, fill it again, then enter the second receipt and the trip distance.
Do not count a partial fill as a whole interval
If either stop was a partial fill, the volume does not represent all the fuel used since the earlier reading. Keep the receipt, but wait until the next full tank before calculating. For several fill-ups, add every litre or gallon between the two full tanks and use the total distance.
US mpg and UK mpg are different
A US gallon is smaller than an imperial gallon, so the same trip produces a lower US mpg number. Choose the gallon used on your receipt or select the result format explicitly. Bortio keeps volume and distance units separate because drivers in the UK often travel in miles but buy fuel in litres.
Turn a fill-up into a useful history
One result is a snapshot. A series shows whether seasons, tyres, traffic or a mechanical problem changed the vehicle. Keep each receipt with its date and odometer reading; the car cost calculator then puts fuel beside maintenance and insurance, while the maintenance log keeps the work that explains sudden changes.
Bortio is available on Android
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