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U.S. Fuel Economy Conversion Table
In the United States, fuel has been measured in Miles per gallon. The fewer miles per gallon, the worse your economy is.
In the decimal system, fuel use is measured as a fuel consumption rate. This rate is in liters per 100 kilometers, or just L/100 km.
If you drive 100 kilometers, and use 5 liters of fuel, your economy is 5 liters / 100 km. The lower the number, the better your fuel economy is.
Since 1 mile = 1.6093 kilometers
and 1 U.S. Gallon = 3.785 liters.
We can create the following formulas:
To change MPG to L / 100km, divide that number into 235.2.
To change L/100 km to MPG, Divide that number into 235.2.
And we have a table.
MPG L/100km
1 235
2 118
3 78.4
4 58.8
5 47.0
6 39.2
7 33.6
8 29.4
9 26.1
10 23.5
11 21.4
12 19.6
13 18.1
14 16.8
15 15.7
16 14.7
17 13.8
18 13.1
19 12.4
20 11.8
21 11.2
22 10.7
23 10.2
24 9.8
25 9.4
L/100km MPG
MPG L/100km
26 9.0
27 8.71
28 8.40
29 8.11
30 7.84
31 7.59
32 7.35
33 7.35
34 6.92
35 6.72
36 6.53
37 6.36
38 6.19
39 6.03
40 5.88
45 5.23
50 4.70
55 4.28
60 3.92
65 3.62
70 3.36
75 3.14
80 2.94
85 2.76
90 2.61
L/100km MPG
For example: 15 MPG becomes 15.7 L/100 km .. also conversely, 15 L/100 km translates to 15.7 MPG.
For British Imperial Gallons, the table and formula are different.