Gal/100 Mi (UK) to MPG (UK)
1 gallon (imperial) per 100 miles equals 100 miles per gallon (imperial).
How to convert gallons (imperial) per 100 miles to miles per gallon (imperial)
Converting gallons (imperial) per 100 miles to miles per gallon (imperial) is not a simple multiplication, so use the formula below.
miles per gallon (imperial) = 100 ÷ gallons (imperial) per 100 miles
Example: 10 gallons (imperial) per 100 miles = 10 miles per gallon (imperial).
Miles per gallon rises as a car gets more efficient, while liters per 100 km falls. The conversion between them is a reciprocal (for US mpg: L/100 km = 235.215 ÷ mpg).
About these units
Gallon (imperial) Per 100 Miles (gal/100 mi (UK))
Imperial gallons used per 100 miles.
Most fuel-economy figures rise when a car gets better, which is why miles per gallon can mislead: going from 10 to 20 miles per gallon saves far more fuel than going from 50 to 60. Quoting consumption per fixed distance avoids that trap, and the United States adopted the idea on its fuel-economy window stickers, which show US gallons per 100 miles. Using imperial gallons of 4.54609 liters gives a British-flavored variant of the same idea, equivalent in spirit to liters per 100 kilometers.
Because lower numbers mean better efficiency, the relationship with distance-per-volume units is a reciprocal. In this converter, kilometers per liter equals 35.4006 divided by the number of imperial gallons per 100 miles, since 100 miles is 160.9344 kilometers and a gallon is 4.54609 liters. For example, 5 gallons per 100 miles is about 7.08 kilometers per liter, or 20 miles per imperial gallon. The unit is rare in practice, and the British continue to rely on miles per imperial gallon alongside liters per 100 kilometers.
1 gallon (imperial) per 100 miles = 35.40061899 kilometers per liter (approximately).
Sources: Wikipedia: Fuel economy in automobiles; NIST SP 811, Appendix B.8 conversion factors
Mile Per Gallon (imperial) (mpg (UK))
Miles traveled on one imperial gallon (4.546 L). The UK still quotes fuel economy this way, so UK mpg figures are about 20% higher than US ones for the same car.
Britain's gallon is a child of the 1824 reform. It was originally defined as the volume of 10 pounds of distilled water at 62 degrees Fahrenheit, taken as 277.274 cubic inches; an 1889 Order in Council changed the figure to 277.463 cubic inches, and in 1976 the UK adopted the metric definition of exactly 4.54609 litres, after Canada had done so. The gallon used in the United States comes from a different, older wine measure, so the two differ by about 20 percent.
One imperial gallon is about 1.2 US gallons, which means that a car rated at 40 mpg in the UK delivers only about 33 mpg on the US scale. Miles per imperial gallon is still the UK's main fuel-economy unit even though petrol is sold by the litre and selling goods by the imperial gallon is no longer legal in Britain. Some Caribbean territories, such as the Cayman Islands and Grenada, still sell petrol by the imperial gallon, while the UAE, Guyana and Myanmar switched to litres in 2010, 2013 and 2014. When a figure says only mpg, check which gallon is meant.
1 mile per gallon (imperial) = 0.3540061899 kilometers per liter (approximately).
Sources: Wikipedia: Imperial gallon; Wikipedia: Fuel economy in automobiles
Related conversions
- MPG (UK) to gal/100 mi (UK) (reverse)
- Gal/100 mi (UK) to km/L
- Gal/100 mi (UK) to MPG (US)
- Gal/100 mi (UK) to L/100 km
- Km/L to MPG (UK)
- MPG (US) to MPG (UK)
- L/100 km to MPG (UK)
- Mi/L to MPG (UK)
- Gal/100 mi (US) to MPG (UK)
- L/mil to MPG (UK)
See all fuel economy units.