Convert between miles per gallon, litres per 100 kilometres and kilometres per litre. Free and exact.
Fuel economy is written in two opposite ways, and this converter handles both.
Liters per 100 kilometers counts fuel for a fixed distance, so a smaller number is a thriftier car. Miles per gallon and kilometers per liter count distance for a fixed amount of fuel, so a larger number is the thriftier one. The two kinds are inverses of each other, which is why the converter divides where the other converters multiply.
Liters per 100 kilometers is the base unit. Every other unit converts through one division, and the same division works in both directions.
Kilometers per liter uses 100 / value. Miles per US gallon uses 235.2145833333333 / value. Miles per Imperial gallon uses 282.4809363318222 / value.
Four units are offered: liter per 100 kilometers, kilometer per liter, mile per US gallon and mile per Imperial gallon. Both gallons are named on the list, because they are different volumes and give different answers. A result is shown to 12 significant digits, and the arithmetic runs in your browser.
30 mpg (US) is 7.84048611111 L/100 km.
Read the same 30 as Imperial mpg and it describes a different car. 30 mpg (Imp) is 24.9802255389 mpg (US), because an Imperial gallon holds more fuel than a US one.
7 L/100 km is 33.6020833333 mpg (US), 40.354419476 mpg (Imp) and 14.2857142857 km/L.
Note the direction. Against the first example the liters figure fell from 7.84048611111 to 7, and the mpg figure rose from 30 to 33.6020833333. Whatever lowers one raises the other.
Divide 235.2145833333333 by the mpg figure. 25 mpg is 9.40858333333 L/100 km, 30 mpg is 7.84048611111, 40 mpg is 5.88036458333, and 50 mpg is 4.70429166667.
The same division runs the other way, because the two units are inverses. 8 L/100 km is 29.4018229167 mpg (US), 6 L/100 km is 39.2024305556 mpg, and 10 L/100 km is 23.5214583333 mpg.
Because the two units measure opposite things. Liters per 100 kilometers asks how much fuel a fixed trip costs, so less is better. Miles per gallon asks how far a fixed amount of fuel goes, so more is better. A car at 4 L/100 km is 58.8036458333 mpg (US), and a car at 12 L/100 km is 19.6012152778 mpg (US).
Both, under separate names, so nothing is assumed for you. The US gallon is 3.785411784 liters and the Imperial gallon is 4.54609 liters, and the Imperial figure is always the larger one for the same car. 30 mpg (US) is 36.0284977651 mpg (Imp), and one mile per US gallon is 1.2009499255 mpg (Imp).
For the volumes on their own, use the Volume Converter.
Divide 100 by the figure to reach liters per 100 kilometers. 20 km/L is 5 L/100 km and 47.0429166667 mpg (US). 15 km/L is 6.66666666667 L/100 km and 35.2821875 mpg (US). One kilometer per liter is 2.35214583333 mpg (US).
The converter reports that the conversion is undefined for the value supplied. A car that uses no fuel travels an unbounded distance on a gallon, so the division has no answer. Negative numbers convert, but they describe nothing real.
Yes to the first, and no to the second. The application is kept in the browser after your first visit, so the page opens and converts with no connection. There is no account, nothing you type reaches a server, and no result is written down.
The constant 235.2145833333333 is not arbitrary. It is the liters in a US gallon divided by the kilometers in a mile, scaled to 100 kilometers, and 282.4809363318222 is the same sum with the Imperial gallon.
Because the conversion divides in both directions, converting a figure and converting it back returns the number you started with.
The two styles also average differently. Over two legs of equal distance, the liters per 100 kilometers of each leg can be averaged directly, because they add up along the route. Averaging the miles per gallon of each leg overstates the car, and the true figure is always the lower one.