30 L/100km to MPG (US)
7.8 mpg
30 L/100km = 7.8 mpg.
MPG (US)
7.8mpg
30 L/100km = 7.8 mpg
The short answer
How many MPG (US) is 30 L/100km?
30 L/100km = 7.8 mpg. MPG (US) = 235.214583 ÷ L/100km, so the working is 235.214583 ÷ 30 = 7.8.
The working
L/100km and MPG (US) are reciprocals of each other, so the conversion is a division rather than a multiplication — which is why the two scales never line up evenly.
MPG (US) = 235.214583 ÷ L/100km 235.214583 ÷ 30 = 7.8
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (mpg) | Off by |
|---|---|---|
| Whole number | 8 | +0.15951 |
| 1 decimal | 7.8 | −0.04049 |
| 2 decimals | 7.84 | −0.00049 |
Round trip: take 7.8 mpg back the other way and you land on 30.1557 L/100km — a drift of 0.1557 L/100km. That gap is the rounding, not the conversion.
Frequently asked questions
What is 30 L/100km in MPG (US)?
30 L/100km is 7.8 MPG (US). MPG (US) = 235.214583 ÷ L/100km, so the working is 235.214583 ÷ 30 = 7.8.
How accurate is 7.8 mpg?
Rounding to 7.8 mpg and converting straight back gives 30.1557 L/100km, a drift of 0.1557 L/100km from the 30 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
L/100km to MPG Converter
Convert L/100km to US MPG — turn a European economy figure into miles per gallon.
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