Convert Imperial Gallons per 100 Miles to Miles per US Gallon

Convert Imperial Gallons per 100 Miles (Imp gal/100mi) to Miles per US Gallon (mpg (US)) instantly and accurately.

Imperial Gallons per 100 Miles (Imp gal/100mi)
Miles per US Gallon (mpg (US))

Conversion Formula

mpg (US) = 83.26741846 รท Imp gal/100mi

About Imperial Gallons per 100 Miles

Imperial gallons per 100 miles is the British volumetric consumption equivalent using the Imperial gallon (4.54609 L). Since the Imperial gallon is ~20.1% larger than the US gallon, a vehicle's Imp gal/100mi is correspondingly smaller than its US gal/100mi. A car at 7 L/100km needs 2.977 US gal/100mi but only 2.478 Imp gal/100mi. The unit appears in UK fleet management software and automotive engineering reports. A 50 mpg(Imp) car uses 2 Imp gal/100mi = 5.650 L/100km. 1 Imp gal/100mi = 4.54609/1.609344 = 2.8248 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 100 Miles (Imp gal/100mi)Miles per US Gallon (mpg (US))
1 Imp gal/100mi83.2674 mpg (US)
2 Imp gal/100mi41.6337 mpg (US)
5 Imp gal/100mi16.6535 mpg (US)
10 Imp gal/100mi8.32674 mpg (US)
25 Imp gal/100mi3.3307 mpg (US)
50 Imp gal/100mi1.66535 mpg (US)
100 Imp gal/100mi0.832674 mpg (US)

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