MPG to km/L Converter
Convert miles per gallon (MPG) to kilometers per liter (km/L). Formula: km/L = MPG (US) × 0.4251.
How to Convert MPG to km/L
This conversion is linear (a simple multiplication), unlike MPG ↔ L/100km. Both units measure distance per unit of fuel, so they scale proportionally.
- km/L = MPG (US) × 0.42514371 (exact: 1.609344 km/mi ÷ 3.785411784 L/gal)
- km/L = MPG (UK) × 0.35400622 (exact: 1.609344 km/mi ÷ 4.54609 L/gal)
The factor 0.4251 comes from exact definitions: 1 mile = 1.609344 km and 1 US gallon = 3.785411784 L.
MPG ↔ km/L Reference Table
Typical fuel-economy values across all four units. Click any MPG value for a dedicated conversion page.
| MPG (US) | km/L | MPG (UK) | L/100km | Category |
|---|---|---|---|---|
| 15 | 6.38 | 18.0 | 15.7 | Poor |
| 20 | 8.50 | 24.0 | 11.8 | Below average |
| 25 | 10.6 | 30.0 | 9.41 | Average |
| 30 | 12.8 | 36.0 | 7.84 | Average |
| 35 | 14.9 | 42.0 | 6.72 | Very good |
| 40 | 17.0 | 48.0 | 5.88 | Very good |
| 50 | 21.3 | 60.0 | 4.70 | Excellent |
| 60 | 25.5 | 72.1 | 3.92 | Excellent |
Common MPG to km/L Conversions
| MPG (US) | km/L | L/100km |
|---|---|---|
| 15 MPG | 6.38 | 15.7 |
| 16 MPG | 6.80 | 14.7 |
| 17 MPG | 7.23 | 13.8 |
| 18 MPG | 7.65 | 13.1 |
| 19 MPG | 8.08 | 12.4 |
| 20 MPG | 8.50 | 11.8 |
| 21 MPG | 8.93 | 11.2 |
| 22 MPG | 9.35 | 10.7 |
| 23 MPG | 9.78 | 10.2 |
| 24 MPG | 10.2 | 9.80 |
| 25 MPG | 10.6 | 9.41 |
| 26 MPG | 11.1 | 9.05 |
| 27 MPG | 11.5 | 8.71 |
| 28 MPG | 11.9 | 8.40 |
| 29 MPG | 12.3 | 8.11 |
| 30 MPG | 12.8 | 7.84 |
| 31 MPG | 13.2 | 7.59 |
| 32 MPG | 13.6 | 7.35 |
| 33 MPG | 14.0 | 7.13 |
| 34 MPG | 14.5 | 6.92 |
| 35 MPG | 14.9 | 6.72 |
| 36 MPG | 15.3 | 6.53 |
| 37 MPG | 15.7 | 6.36 |
| 38 MPG | 16.2 | 6.19 |
| 39 MPG | 16.6 | 6.03 |
| 40 MPG | 17.0 | 5.88 |
| 41 MPG | 17.4 | 5.74 |
| 42 MPG | 17.9 | 5.60 |
| 43 MPG | 18.3 | 5.47 |
| 44 MPG | 18.7 | 5.35 |
| 45 MPG | 19.1 | 5.23 |
| 46 MPG | 19.6 | 5.11 |
| 47 MPG | 20.0 | 5.00 |
| 48 MPG | 20.4 | 4.90 |
| 49 MPG | 20.8 | 4.80 |
| 50 MPG | 21.3 | 4.70 |
| 51 MPG | 21.7 | 4.61 |
| 52 MPG | 22.1 | 4.52 |
| 53 MPG | 22.5 | 4.44 |
| 54 MPG | 23.0 | 4.36 |
| 55 MPG | 23.4 | 4.28 |
| 60 MPG | 25.5 | 3.92 |
| 65 MPG | 27.6 | 3.62 |
| 70 MPG | 29.8 | 3.36 |
| 80 MPG | 34.0 | 2.94 |
| 100 MPG | 42.5 | 2.35 |
Frequently Asked Questions
How to convert MPG to km/L?
Multiply MPG (US) by 0.4251. Example: 30 × 0.4251 = 12.75 km/L. The factor comes from 1.609344 km/mi ÷ 3.785411784 L/gallon.
What is 30 MPG in km/L?
30 MPG (US) = 30 × 0.4251 = 12.75 km/L. In other units, 30 MPG = 36.0 MPG (UK) = 7.84 L/100km.
Which countries use km/L?
km/L is the primary fuel-economy metric in India (ARAI certification), Japan (JC08 and WLTC cycles), South Korea, and parts of Latin America including Brazil (INMETRO).
Related Fuel Economy Converters
Where km/L Is Used
Kilometers per liter (km/L) is the official fuel-economy unit across several large automotive markets. In India, the Automotive Research Association of India (ARAI) certifies new cars with a km/L rating commonly shown in marketing materials and spec sheets. In Japan, manufacturers publish km/L figures from the JC08 test cycle (pre-2018 models) or the newer WLTC cycle (2018 onward). South Korea, the Philippines and Brazil (through INMETRO’s energy-efficiency programme) also use km/L as the primary retail metric.
For anyone cross-shopping vehicles between these markets and the US, the conversion between MPG and km/L is straightforward because both units are directly proportional — unlike the inverse relationship between MPG and L/100km. A US car rated at 30 MPG is exactly the same efficiency as a Japanese car rated at 12.75 km/L.
Mileage in India: ARAI vs Real World
India’s ARAI test figures are widely reported to be 15–20% higher than real-world driving, similar to the gap seen with the older NEDC cycle in Europe. A hatchback advertised as 22 km/L might average 17–18 km/L in city driving with air-conditioning on. When you see Indian spec sheets quoting 25+ km/L (58+ MPG), expect the real-world figure to be around 20 km/L (47 MPG).
Japanese Fuel Economy Labels
Japanese cars sold before 2018 were rated on the JC08 cycle, which tended to inflate numbers (similar to Europe’s old NEDC). Cars sold from 2018 onward use the WLTC cycle, which matches WLTP and gives more realistic figures. When comparing a 2016 Japanese car at 20 km/L to a 2020 model at 18 km/L, the newer car is not necessarily less efficient — it is simply tested more honestly.
Reference Table
| MPG (US) | km/L | Interpretation |
|---|---|---|
| 15 | 6.4 | Large truck, SUV |
| 20 | 8.5 | Midsize SUV |
| 25 | 10.6 | Midsize sedan |
| 30 | 12.8 | Average midsize car |
| 40 | 17.0 | Very efficient small car |
| 50 | 21.3 | Hybrid sedan |
| 60 | 25.5 | Plug-in hybrid / Best-in-class |
Quick Mental Math
Since the factor is 0.4251, you can estimate km/L by taking 40% of the MPG value and adding a small correction. For example, 30 MPG → 40% of 30 is 12, plus roughly 0.7 gives 12.7 km/L (actual: 12.75). For higher precision, remember that 1 MPG = 0.4251 km/L, so a 10 MPG increase is about 4.25 km/L.
Full Conversion Table
Need a printable reference? See the full MPG to km/L conversion table with pre-calculated values, CSV download, and print-friendly layout.
