AI Calculator Tool

Imperial Gallon to US Gallon Converter

Convert UK imperial gallons to US gallons. Multiply by 1.20095—imp gal is ~20% larger. For fuel economy and import specs.

How to Convert Imperial gallon to Us gallon

Multiply imperial gallons by 1.20095 (1 imp gal = 1.20095 US gal).

Conversion Formula:

value * 1.20095

Conversion Examples

Example: 1 imp gal to US gal

  1. 1 × 1.20095 ≈ 1.20 US gal

1 imp gal ≈ 1.20 US gal

Imperial gallon is larger.

Example: 10 imp gal to US gal

  1. 10 × 1.20095 ≈ 12.01 US gal

10 imp gal ≈ 12.01 US gal

Typical tank comparison.

Conversion Chart

Imperial gallonUs gallon
11
22
34
45
56
67
78
810
911
1012
1518
2024
3036
6072
100120

Conversion Formula

Multiply imperial gallons by **1.20095** for US gallons.

Quick Conversion Tip

Imp gal × 1.2 ≈ US gal (quick estimate).

Unit Definitions

Imperial Gallon (imp gal)

An imperial gallon is a UK unit of volume historically used for fuel and beverages, larger than the US gallon.

1 imperial gallon = 4.54609 liters ≈ 1.20095 US gallons = 160 imperial fluid ounces

US Gallon (gal)

A US gallon is the standard gallon used in the United States for liquids such as gasoline, milk, and water.

1 US gallon = 3.78541 liters = 231 cubic inches = 16 US cups

Common Use Cases

  • UK fuel prices and economy vs US gallons.
  • Import vehicle tank capacity labels.
  • Brewing and beverage volume (UK vs US).
  • Travel and fuel planning between countries.

Understanding the Conversion

1 imperial gallon ≈ 1.201 US gallons (4.546 L vs 3.785 L). Multiply imp gal by 1.20095.

Example: 10 imp gal ≈ 12.01 US gal. Essential when comparing UK fuel economy (mpg) to US gallons or converting tank sizes abroad.

Divide US gallons by 1.20095 for imperial gallons.

FAQs

How many US gallons in one imperial gallon?

About 1.20095 US gallons.

Which gallon is bigger?

The imperial (UK) gallon—about 4.546 L vs 3.785 L for US.

How do I convert imp gal to US gal?

Multiply imperial gallons by 1.20095.