45 US MPG to UK MPG
| 45 MPG (US) | = | 54.0 MPG (UK / Imperial) |
| 45 MPG (US) | = | 5.23 L/100km |
| 45 MPG (US) | = | 19.1 km/L |
How to Convert US MPG to UK MPG
The conversion is linear — the difference is entirely in the size of the gallon, not in the miles.
- MPG (UK) = MPG (US) × 1.20095042
The factor 1.20095 is the exact ratio between the Imperial gallon (4.54609 L) and the US gallon (3.785411784 L).
Applying the formula to 45 MPG (US): 45 × 1.20095 = 54.0 MPG (UK).
Is 45 MPG (US) good?
45 MPG (US) is considered Very good — typical of efficient sedans and compact cars. In Imperial terms, that’s 54.0 MPG (UK). In metric terms, 5.23 L/100km or 19.1 km/L.
Need a different value? Use our US MPG to UK MPG Converter.
Similar Conversions
| MPG (US) | MPG (UK) | L/100km |
|---|---|---|
| 40 MPG | 48.0 | 5.88 |
| 41 MPG | 49.2 | 5.74 |
| 42 MPG | 50.4 | 5.60 |
| 43 MPG | 51.6 | 5.47 |
| 44 MPG | 52.8 | 5.35 |
| 46 MPG | 55.2 | 5.11 |
| 47 MPG | 56.4 | 5.00 |
| 48 MPG | 57.6 | 4.90 |
| 49 MPG | 58.8 | 4.80 |
| 50 MPG | 60.0 | 4.70 |
Related Fuel Economy Converters
Conversion factors verified against NIST, BIPM
Based on SI definitions (BIPM).
Last reviewed: March 2026
