How US MPG to Imperial MPG Converter Works?
This tool works by multiplying US miles per gallon (MPG) by 1.20095. The factor reflects the larger size of the imperial gallon.
Enter the US MPG rating
Type the MPG from a US window sticker or US review, for example 30 US MPG.
Apply the conversion factor
The tool multiplies by 1.20095, the ratio of imperial to US gallons.
Read the imperial MPG
The tool returns MPG in UK imperial gallons.
Compare with UK figures
Set the result beside UK brochure or review figures.
US MPG to Imperial MPG Converter Formula
The formula is Imperial MPG = US MPG × 1.20095.
Imperial MPG = US MPG × 1.20095Formula variables
- US MPG
- Miles per US gallon (3.785 L).
- 1.20095
- Imperial gallon (4.546 L) ÷ US gallon (3.785 L).
Worked example
- US MPG Rating: 30 US MPG
- Multiply 30 by 1.20095: 30 × 1.20095 = 36.03 imperial MPG.
Result: 36.03 (Imperial MPG)
The same car gets a higher MPG number in the UK, not better fuel economy. Divide imperial MPG by 1.20095 to convert back to US MPG.
US MPG to Imperial MPG Converter Conversion Table
The table lists imperial MPG equivalents for 7 common US MPG ratings.
| US MPG Rating (US MPG) | Result (Imperial MPG) |
|---|---|
| 15 US MPG | 18.01 |
| 20 US MPG | 24.02 |
| 25 US MPG | 30.02 |
| 30 US MPG | 36.03 |
| 35 US MPG | 42.03 |
| 40 US MPG | 48.04 |
| 50 US MPG | 60.05 |
A 50 US MPG hybrid rates 60.05 MPG in imperial units, the format used in UK car reviews.
What is US MPG to Imperial MPG Converter?
The US MPG to Imperial MPG Converter is a tool that converts fuel economy from US gallons to UK imperial gallons. The tool makes US and UK MPG figures comparable.
The US gallon holds 3.785 liters, while the imperial gallon holds 4.546 liters. MPG figures in the 2 systems differ by about 20% for the same vehicle.
Canada and the UK sell fuel in liters but often quote fuel economy in imperial MPG, which makes this conversion common.
What are the uses of US MPG to Imperial MPG Converter?
There are 4 main uses of the US MPG to Imperial MPG Converter: comparing US and UK car reviews, importing vehicles, reading Canadian fuel guides, and checking forum figures.
Comparing US and UK car reviews
Readers align US and UK MPG figures for the same model.
Importing vehicles
Buyers convert US ratings when importing cars to the UK.
Reading Canadian fuel guides
Drivers compare older Canadian imperial MPG figures with US ratings.
Checking forum figures
Owners convert MPG posted on international forums.
Need every metric in one place? Open the main MPG Cost Calculator or browse all 101 fuel calculators.