40 MPG to Miles per Litre
| 40 MPG (UK) | = | 8.80 miles per litre |
| 40 MPG (UK) | = | 7.06 L/100km |
| 40 MPG (UK) | = | 14.2 km/L |
| 40 MPG (UK) | = | 33.3 MPG (US) |
How to Convert MPG to Miles per Litre
The conversion is linear: a litre is a fixed fraction of a gallon, so dividing MPG by the litres-per-gallon constant gives miles per litre directly.
- MPL = MPG (UK) ÷ 4.54609
- MPL = MPG (US) ÷ 3.785411784
Applying the formula to 40 MPG (UK): 40 ÷ 4.54609 = 8.80 miles per litre.
Is 40 MPG (UK) good?
40 MPG (UK) is considered Good — efficient petrol car. That works out to 8.80 miles per litre, 7.06 L/100km, or 14.2 km/L. In US terms, 40 MPG (UK) = 33.3 MPG (US).
Need a different value? Use our MPG to Miles per Litre Converter.
Similar Conversions
| MPG (UK) | MPL | L/100km |
|---|---|---|
| 35 MPG | 7.70 | 8.07 |
| 36 MPG | 7.92 | 7.85 |
| 37 MPG | 8.14 | 7.63 |
| 38 MPG | 8.36 | 7.43 |
| 39 MPG | 8.58 | 7.24 |
| 41 MPG | 9.02 | 6.89 |
| 42 MPG | 9.24 | 6.73 |
| 43 MPG | 9.46 | 6.57 |
| 44 MPG | 9.68 | 6.42 |
| 45 MPG | 9.90 | 6.28 |
Related Fuel Economy Converters
Miles per Litre to MPG
Reverse conversion: miles per litre to miles per gallon (UK and US).
MPG (UK) to L/100km
Convert Imperial MPG to litres per 100 km for European comparisons.
MPG to L/100km
Miles per gallon (US/UK) to litres per 100 km.
MPG Calculator
Calculate your car’s MPG from distance and fuel used.
Conversion factors verified against NIST, BIPM
Based on SI definitions (BIPM).
Last reviewed: March 2026
