Miles per US Gallon to Miles per Imperial Gallon

Free instant miles per us gallon to miles per imperial gallon converter. 1 mpg = 1.20095 mpg.

1.20095
Formula
1 mpg = 1.20095 mpg

Common Miles per US Gallon to Miles per Imperial Gallon values

Miles per US Gallon (mpg)Miles per Imperial Gallon (mpg)
11.20095
56.00475
1012.0095
2530.0237
5060.0475
100120.095
500600.475
10001200.95

How does Miles per US Gallon to Miles per Imperial Gallon conversion work?

Type a value in the Miles per US Gallon (mpg) field and the equivalent in Miles per Imperial Gallon (mpg) appears instantly to the right. The math uses the exact formula shown above — no rounding errors, no approximations beyond standard floating-point precision. Use the swap button to flip the units and see the inverse conversion.

Miles per US Gallon. The standard fuel-economy unit in the US. HIGHER is better — 30 mpg is decent; 50+ mpg is excellent.

Miles per Imperial Gallon. The UK fuel-economy unit. About 1.2× higher than US mpg because the imperial gallon is bigger. 40 UK mpg ≈ 33 US mpg.

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No submit button — the result updates as you type. Math runs entirely in your browser, so it’s as fast as your device.

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Works in any modern browser — Mac, Windows, Linux, iPhone, Android, tablets. No installation, no signup.

🎯 Accurate conversions

Conversion factors come from the official standard (NIST, BIPM, ISO definitions where applicable). Values are precise to standard floating-point limits.

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Frequently asked

What is the formula for converting Miles per US Gallon to Miles per Imperial Gallon?+
The formula is: 1 mpg = 1.20095 mpg. Type any value into the calculator above and the result appears instantly.
How do I convert Miles per Imperial Gallon back to Miles per US Gallon?+
Click the swap button (⇄) above to go to the Miles per Imperial Gallon → Miles per US Gallon converter, or use the inverse formula derived from the one shown.

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