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Specs & Conversions

MPG to L/100km Converter

Comparing a US fuel-economy figure with a European or Asian one? Enter the MPG (US gallons) and we’ll convert it to liters per 100 km and kilometers per liter.

Quick answer

To convert US MPG to L/100km, divide 235.21 by the MPG. For example, 30 MPG ≈ 7.84 L/100km and 40 MPG ≈ 5.88 L/100km. The two are reciprocals, so a higher MPG gives a lower (better) L/100km.

MPG to L/100km Converter
Liters per 100 kmLive

How this calculator works

MPG and L/100km are inverse measures, so the conversion isn’t linear: L/100km = 235.21 ÷ MPG. A higher MPG means a lower L/100km (less fuel used). We also give km/L, which like MPG goes up as the car gets thriftier.

What changes the number

  • This uses the US gallon (3.785 L). Imperial (UK) gallons are larger, so UK MPG figures look higher for the same car — don’t mix them.
  • L/100km is “lower is better”; MPG and km/L are “higher is better.” It’s easy to flip them by mistake.
  • For quick mental math, 235 ÷ MPG is close enough.

MPG to L/100km conversion chart

US gallons. Read across from your MPG figure — L/100km is lower-is-better, km/L is higher-is-better.

MPG (US)L/100kmkm/L
1023.524.25
1121.384.68
1219.605.10
1318.095.53
1416.805.95
1515.686.38
1614.706.80
1713.847.23
1813.077.65
1912.388.08
2011.768.50
2111.208.93
2210.699.35
2310.239.78
249.8010.20
259.4110.63
269.0511.05
278.7111.48
288.4011.90
298.1112.33
307.8412.75
317.5913.18
327.3513.60
337.1314.03
346.9214.45
356.7214.88
366.5315.31
376.3615.73
386.1916.16
396.0316.58
405.8817.01
415.7417.43
425.6017.86
435.4718.28
445.3518.71
455.2319.13
465.1119.56
475.0019.98
484.9020.41
494.8020.83
504.7021.26

L/100km to MPG conversion chart

The reverse direction, plus Imperial (UK) MPG — the same car reads about 20% higher in Imperial gallons, which is why a UK review and a US one quote different numbers for one vehicle.

L/100kmMPG (US)MPG (Imperial)
3.078.494.2
3.567.280.7
4.058.870.6
4.552.362.8
5.047.056.5
5.542.851.4
6.039.247.1
6.536.243.5
7.033.640.4
7.531.437.7
8.029.435.3
8.527.733.2
9.026.131.4
9.524.829.7
10.023.528.2
11.021.425.7
12.019.623.5
13.018.121.7
14.016.820.2
15.015.718.8
16.014.717.7
18.013.115.7
20.011.814.1

Frequently asked questions

Why isn’t the conversion a simple multiplier?

Because the two units measure opposite things — distance per fuel vs fuel per distance. That makes them reciprocals, so you divide a constant (235.21) by the MPG rather than scaling it.

Is this US or Imperial gallons?

US gallons. A UK Imperial gallon is about 20% larger, so a UK “50 mpg” is not the same as a US “50 mpg.” Use the US figure here.

What’s a good L/100km?

Lower is better. An efficient modern car is around 6–8 L/100km; a hybrid can dip to 4–5; large trucks run 12+.

What is 30 MPG in L/100km?

30 MPG (US) is 7.84 L/100km, or 12.75 km/L. The other figures people look up most: 15 MPG = 15.68, 16 MPG = 14.70, 20 MPG = 11.76, 22 MPG = 10.69, 25 MPG = 9.41, 35 MPG = 6.72, and 40 MPG = 5.88 L/100km. The full chart above covers every value from 10 to 50 MPG.

How do I convert L/100km back to MPG?

The same constant, the other way around: MPG (US) = 235.21 ÷ L/100km. So 7 L/100km is about 33.6 MPG, 8 L/100km is 29.4, and 10 L/100km is 23.5. For Imperial (UK) MPG, divide 282.48 by the L/100km figure instead.

How do I convert Imperial (UK) MPG to L/100km?

Divide 282.48 by the Imperial MPG — the constant differs from the US one because a UK gallon is about 20% larger. A UK-quoted 50 mpg works out to roughly 5.65 L/100km, which is about 41.6 US MPG. Same car, three different numbers, which is exactly how spec sheets mislead people.