Miles per imperial gallon to US gallons per 100 miles
Convert Miles per imperial gallon to US gallons per 100 miles instantly. Free online fuel economy unit converter with exact formula, conversion table and FAQ.
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Formula
1 mpg imp = 120.0949926 gal/100 mi
gal/100 mi = 120.0949926 ÷ mpg imp
mpg imp = 120.0949926 ÷ gal/100 mi
Conversion table
| 1 mpg imp | 120.094993 gal/100 mi |
| 2 mpg imp | 60.047496 gal/100 mi |
| 5 mpg imp | 24.018999 gal/100 mi |
| 10 mpg imp | 12.009499 gal/100 mi |
| 20 mpg imp | 6.00475 gal/100 mi |
| 50 mpg imp | 2.4019 gal/100 mi |
| 100 mpg imp | 1.20095 gal/100 mi |
Related conversions
- 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
- 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
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Frequently asked questions
How many us gallons per 100 miles are in one miles per imperial gallon?
One mpg imp equals 120.0949926 gal/100 mi (this pair inverts, since one measures distance per volume and the other volume per distance).
How do I convert miles per imperial gallon to us gallons per 100 miles?
Divide 120.0949926 by the miles per imperial gallon value to get us gallons per 100 miles, and divide 120.0949926 by the us gallons per 100 miles value to get back miles per imperial gallon. 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 miles per imperial gallon and us gallons per 100 miles, so the result shown is mathematically precise (rounded only for display).
When is miles per imperial gallon to us gallons per 100 miles 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
Miles per imperial gallon and US gallons per 100 miles are both units used to measure fuel economy. 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 (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 is a distance-per-volume efficiency unit while us gallons per 100 miles is a volume-per-distance consumption unit, so converting between them means inverting the value rather than multiplying by a flat factor: 1 mpg imp = 120.0949926 gal/100 mi. This relationship stays accurate for automotive fuel efficiency ratings, vehicle comparisons and shopping, as well as EPA, WLTP and other international fuel economy standards.