Convert Imperial Gallons per Mile to Miles per US Gallon
Convert Imperial Gallons per Mile (Imp gal/mi) to Miles per US Gallon (mpg (US)) instantly and accurately.
Conversion Formula
mpg (US) = 0.8326741846 ÷ Imp gal/mi
About Imperial Gallons per Mile
Imperial gallons per mile is the British counterpart, using the 4.54609 L Imperial gallon. 1 Imp gal/mi = 4.54609/1.609344 × 100 = 282.481 L/100km - among the largest fuel-consumption values in practical use, representing large vessels and heavy machinery. It appears in older Royal Navy vessel technical logs and historical British railway and steam-locomotive records. As mpg(Imp) and gal/mi are reciprocals, a 50 mpg(Imp) car uses exactly 0.02 Imp gal/mi = 5.650 L/100km. 1 Imp gal/mi = 282.481 L/100km.
About Miles per US Gallon
Miles per US gallon (mpg(US)) is the US and Canadian standard, displayed on every EPA Monroney sticker and used in CAFE regulations. The US gallon = 3.785411784 L; 1 mile = 1.609344 km. 2026 CAFE passenger car standard: ~49 mpg. Toyota Prius Prime: 52 mpg; Tesla Model 3: 132 MPGe. Historical: Ford Model T 21-25 mpg; 1973 US full-size cars 10-15 mpg. NASCAR at race speed: 4-5 mpg; Class 8 semi: 5-8 mpg. L/100km = 235.21458/mpg(US): 30 mpg = 7.84 L/100km; 50 mpg = 4.71 L/100km.
Quick Reference Table
| Imperial Gallons per Mile (Imp gal/mi) | Miles per US Gallon (mpg (US)) |
|---|---|
| 1 Imp gal/mi | 0.832674 mpg (US) |
| 2 Imp gal/mi | 0.416337 mpg (US) |
| 5 Imp gal/mi | 0.166535 mpg (US) |
| 10 Imp gal/mi | 0.0832674 mpg (US) |
| 25 Imp gal/mi | 0.033307 mpg (US) |
| 50 Imp gal/mi | 0.0166535 mpg (US) |
| 100 Imp gal/mi | 0.00832674 mpg (US) |