US gallons per 100 miles to Miles per imperial gallon
Convert US gallons per 100 miles to Miles per imperial gallon instantly. Free online fuel economy unit converter with exact formula, conversion table and FAQ.
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Formula
1 gal/100 mi = 120.0949926 mpg imp
mpg imp = 120.0949926 ÷ gal/100 mi
gal/100 mi = 120.0949926 ÷ mpg imp
Conversion table
| 1 gal/100 mi | 120.094993 mpg imp |
| 2 gal/100 mi | 60.047496 mpg imp |
| 5 gal/100 mi | 24.018999 mpg imp |
| 10 gal/100 mi | 12.009499 mpg imp |
| 20 gal/100 mi | 6.00475 mpg imp |
| 50 gal/100 mi | 2.4019 mpg imp |
| 100 gal/100 mi | 1.20095 mpg imp |
Related conversions
- US gallons per 100 miles → Miles per US gallon
- US gallons per 100 miles → Kilometers per liter
- US gallons per 100 miles → Meters per liter
- US gallons per 100 miles → Liters per 100 km
- US gallons per 100 miles → Liters per km
- Miles per imperial gallon → Miles per US gallon
- Miles per imperial gallon → Kilometers per liter
- Miles per imperial gallon → Meters per liter
- Miles per imperial gallon → Liters per 100 km
- Miles per imperial gallon → Liters per km
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Frequently asked questions
How many miles per imperial gallon are in one us gallons per 100 miles?
One gal/100 mi equals 120.0949926 mpg imp (this pair inverts, since one measures distance per volume and the other volume per distance).
How do I convert us gallons per 100 miles to miles per imperial gallon?
Divide 120.0949926 by the us gallons per 100 miles value to get miles per imperial gallon, and divide 120.0949926 by the miles per imperial gallon value to get back us gallons per 100 miles. This "invert the constant" rule works both ways because one unit is distance-per-volume and the other is volume-per-distance.
Is this conversion exact?
Yes. This conversion uses the exact defined relationship between us gallons per 100 miles and miles per imperial gallon, so the result shown is mathematically precise (rounded only for display).
When is us gallons per 100 miles to miles per imperial gallon conversion commonly used?
It is commonly used in automotive fuel efficiency ratings, vehicle comparisons and shopping, as well as EPA, WLTP and other international fuel economy standards.
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About this conversion
US gallons per 100 miles and Miles per imperial gallon are both units used to measure fuel economy. US gallons per 100 miles (gal/100 mi) measures how many US gallons of fuel a vehicle consumes over 100 miles; a lower number means better efficiency. It is occasionally used in the United States for consumption-style comparisons. Miles per imperial gallon (mpg imp) measures how many miles a vehicle travels using one imperial (UK) gallon of fuel; a higher number means better efficiency. It is used mainly in the United Kingdom and other Commonwealth countries. US gallons per 100 miles is a distance-per-volume efficiency unit while miles per imperial gallon is a volume-per-distance consumption unit, so converting between them means inverting the value rather than multiplying by a flat factor: 1 gal/100 mi = 120.0949926 mpg imp. This relationship stays accurate for automotive fuel efficiency ratings, vehicle comparisons and shopping, as well as EPA, WLTP and other international fuel economy standards.