CONVERSION · FUEL & TRAVEL

Imperial miles per gallon to us miles per gallon converter

Convert imperial miles per gallon to us miles per gallon with an editable calculator, worked example, formula and reference table. Check the unit definitions before you convert.

Updated · How we check
TRY YOUR OWN NUMBER Reverse conversion

Use a decimal point, such as 2.5. Enter a number greater than zero. Check whether gallons are US or Imperial.

US miles per gallon≈ 24.98022554US mpg

Formula

US mpg ≈ UK mpg × 0.8326741846

Worked example

Convert 30 UK mpg to US mpg:

30 UK mpg ≈ 24.98022554 US mpg

Multiply your UK mpg value by the factor above. The calculator uses the full conversion factor before rounding the displayed answer.

Imperial miles per gallon to us miles per gallon table

Reference values rounded to 10 significant digits. Use the converter above for other amounts.

Approximate conversion reference
Imperial miles per gallon (UK mpg)US miles per gallon (US mpg)
0.1≈ 0.08326741846
0.5≈ 0.4163370923
1≈ 0.8326741846
2≈ 1.665348369
5≈ 4.163370923
10≈ 8.326741846
25≈ 20.81685462
50≈ 41.63370923
100≈ 83.26741846
1000≈ 832.6741846

Understanding imperial miles per gallon

Imperial mpg uses the Imperial gallon of 4.54609 liters. It is numerically higher than US mpg for the same vehicle efficiency because an Imperial gallon holds more fuel.

Understanding us miles per gallon

US mpg uses the US liquid gallon of 3.785411784 liters and the international mile of 1.609344 kilometers. It must not be compared numerically with Imperial mpg without conversion.

Precision and rounding

The calculator keeps decimal precision during the conversion. Displayed values use up to 10 significant digits; an approximation sign marks the reference results. Keep extra digits until your final measurement or purchase decision.

References

Definitions and method references. Example rates and prices on this page are editable assumptions.