Miles per US gallon to US gallons per 100 miles
Convert Miles per US 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 = 100 gal/100 mi
gal/100 mi = 100 ÷ mpg
mpg = 100 ÷ gal/100 mi
Conversion table
| 1 mpg | 100 gal/100 mi |
| 2 mpg | 50 gal/100 mi |
| 5 mpg | 20 gal/100 mi |
| 10 mpg | 10 gal/100 mi |
| 20 mpg | 5 gal/100 mi |
| 50 mpg | 2 gal/100 mi |
| 100 mpg | 1 gal/100 mi |
Related conversions
- Miles per US gallon → Miles per imperial gallon
- Miles per US gallon → Kilometers per liter
- Miles per US gallon → Meters per liter
- Miles per US gallon → Liters per 100 km
- Miles per US gallon → Liters per km
- US gallons per 100 miles → Miles per imperial 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 us gallon?
One mpg equals 100 gal/100 mi (this pair inverts, since one measures distance per volume and the other volume per distance).
How do I convert miles per us gallon to us gallons per 100 miles?
Divide 100 by the miles per us gallon value to get us gallons per 100 miles, and divide 100 by the us gallons per 100 miles value to get back miles per us 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 us gallon and us gallons per 100 miles, so the result shown is mathematically precise (rounded only for display).
When is miles per us 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 US gallon and US gallons per 100 miles are both units used to measure fuel economy. Miles per US gallon (mpg) measures how many miles a vehicle travels using one US gallon of fuel; a higher number means better efficiency. It is the standard fuel economy unit used in the United States. 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 US 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 = 100 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.