Convert UK Gallon to Cubic Meter (gal (UK) → m³)

Converting UK gallons to cubic meters is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in UK gallons

   Start with the number of UK gallons (gal (UK)) you want to convert.
2. 2
   Multiply by 0.004546

   The conversion factor from gal (UK) to m³ is 0.004546. Multiply your value by this number.
3. 3
   Read the result in cubic meters

   The result is your value in cubic meters (m³).

Multiply the value in UK gallons by 0.004546. For the reverse direction, multiply by 219.96925.

• ✓1 UK gallon = 4.54609 L exactly = 160 UK fluid ounces.
• ✓1 UK gallon ≈ 1.201 US gallons.
• ✓UK mpg × 0.832 = US mpg (same car, different unit).

• ✗Comparing UK mpg with US mpg directly — UK figures are about 20% higher for the same car.
• ✗Using 4.5 L instead of 4.546 L for precise conversion.
• ✗Assuming modern UK car ads quote US gallons — they always use UK gallons.

What is the UK Gallon?

The UK imperial gallon equals exactly 4.54609 liters and is approximately 20% larger than the US gallon. Established by the British Weights and Measures Act of 1824 to standardize earlier ale and corn gallons, the imperial gallon was designed so that 10 pounds of pure water at 62°F occupied exactly 1 gallon. Although the United Kingdom has officially adopted the liter for fuel sales since 1995, the imperial gallon persists in everyday speech ('miles per gallon' for car fuel economy) and remains the standard unit in some Caribbean and Pacific Commonwealth countries. The imperial gallon relates to the US gallon (1 imp gal ≈ 1.201 US gal), the imperial quart (4 imp qt = 1 imp gal), the imperial pint (8 imp pt = 1 imp gal — the famous British pint of beer), and the liter (1 imp gal ≈ 4.546 L).

• UK fuel economy in miles per gallon (UK mpg)
• Older British industrial and brewing contexts
• Commonwealth countries that retain imperial measures

What is the Cubic Meter?

The cubic meter equals exactly 1,000 liters and is the SI unit of volume, used for water utilities, construction materials, shipping containers, gas volumes, and industrial-scale measurements. Domestic water bills typically show consumption in cubic meters (a typical household uses 5–15 m³ per month), and natural-gas billing also uses m³. Concrete is delivered by the cubic meter, and shipping containers have internal volumes of about 33 m³ (20-ft) or 67 m³ (40-ft). The cubic meter is the volume of a cube measuring 1 meter on each side. It relates to the liter (1 m³ = 1,000 L), the cubic centimeter (1 m³ = 1,000,000 cm³), the cubic foot (1 m³ ≈ 35.31 ft³), and the US gallon (1 m³ ≈ 264.17 gal). Truck-cargo capacity, swimming-pool size, and natural-gas reserves are all commonly expressed in cubic meters.

• Household water and gas consumption on utility bills
• Concrete ordering for construction projects
• Shipping container and freight capacity