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UK Gallons to US Fluid Ounces (imp gal to fl oz) Converter

1 UK gallon (imp gal) = 153.722 US fluid ounces (fl oz). To convert UK gallons to US fluid ounces, multiply by 153.722: 25 imp gal × 153.722 = 3,843.04 fl oz.

1 imp gal = 153.7215902697 fl oz
Convert the other way: US Fluid Ounces to UK Gallons

Quick facts

How to convert UK gallons to US fluid ounces

  1. Write down the number of UK gallons you have.
  2. Multiply it by 153.722 (the number of US fluid ounces in one UK gallon).
  3. Check the answer: it should be larger than the number you started with.
fl oz = imp gal × 153.722

Worked example: 25 imp gal × 153.722 = 3843.04 fl oz.

To convert US fluid ounces back to UK gallons, multiply by 0.00650527, or divide by 153.722.

Source: NIST Handbook 44, Appendix C, and NIST SP 811 (US customary volume units).

UK Gallons to US Fluid Ounces conversion table

UK Gallons to US Fluid Ounces conversion table
UK Gallons [imp gal]US Fluid Ounces [fl oz]
0.01 imp gal1.5372159027 fl oz
0.1 imp gal15.372159027 fl oz
1 imp gal153.7215902697 fl oz
2 imp gal307.4431805394 fl oz
3 imp gal461.1647708091 fl oz
5 imp gal768.6079513485 fl oz
10 imp gal1537.215902697 fl oz
20 imp gal3074.431805394 fl oz
50 imp gal7686.0795134849 fl oz
100 imp gal15372.1590269698 fl oz
1000 imp gal153721.5902696985 fl oz

imp gal to fl oz chart from 1 to 100

US Fluid Ounces to UK Gallons conversion table

US Fluid Ounces to UK Gallons conversion table
US Fluid Ounces [fl oz]UK Gallons [imp gal]
0.01 fl oz0.0000650527 imp gal
0.1 fl oz0.0006505267 imp gal
1 fl oz0.0065052671 imp gal
2 fl oz0.0130105342 imp gal
3 fl oz0.0195158012 imp gal
5 fl oz0.0325263354 imp gal
10 fl oz0.0650526708 imp gal
20 fl oz0.1301053415 imp gal
50 fl oz0.3252633538 imp gal
100 fl oz0.6505267076 imp gal
1000 fl oz6.5052670757 imp gal

UK Gallons vs US Fluid Ounces

UK GallonUS Fluid Ounce
Symbolimp galfl oz
Equals1 imp gal = 153.722 fl oz1 fl oz = 0.00650527 imp gal

What is a UK gallon?

The imperial gallon, defined as exactly 4.54609 litres (UK Weights and Measures Act 1985); about 20% larger than the US gallon. Used in the UK and Canada for fuel economy (miles per gallon), garden and aquarium volumes, and older fuel prices.

What is a US fluid ounce?

A US customary unit equal to 1/16 of a US pint. Used in the US for beverage and bottle sizes.

Who Converts UK Gallons to US Fluid Ounces?

UK gallons are used mainly in the UK (pub pints, fuel economy in mpg) and older Canadian recipes, while US fluid ounces are used mainly in the United States. This conversion bridges the US customary and metric systems, so it comes up whenever a figure crosses the US border with Canada or the Atlantic with the UK: product specifications, travel, recipes, school work and trade.

How big is 1 imp gal compared with 1 fl oz?

1 imp gal is 153.722 times the size of 1 fl oz, so the number gets bigger when you convert UK gallons to US fluid ounces.

UK Gallons to US Fluid Ounces without a calculator

Real-world imp gal to fl oz examples

Everyday UK gallons and US fluid ounces
ExampleUK GallonsUS Fluid Ounces
One imperial gallon1 imp gal153.722 fl oz
A small aquarium10 imp gal1537.22 fl oz
A garden water butt45 imp gal6917.47 fl oz
A can of soda0.0780632 imp gal12 fl oz
A US pint glass0.104084 imp gal16 fl oz
One cup0.0520421 imp gal8 fl oz

How exact is the imp gal to fl oz factor?

The factor is exact by definition, so any error comes only from rounding. Keep at least 4 significant figures for school work, and the full factor for anything legal or commercial.

Mistakes to avoid

Background on UK gallons and US fluid ounces

The imperial gallon was introduced in 1824 and is defined as exactly 4.54609 litres.

What people convert next

Related conversions you may need next: us gallons to us fluid ounces, uk gallons to uk fluid ounces, us fluid ounces to milliliters and uk gallons to liters. The full volume converter lists every unit.

On pakmath.com, the scientific calculator is a useful next step, as is the percentage calculator; Adzita offers a free fuel cost calculator.

Frequently asked questions

How many US fluid ounces are in a UK gallon?

There are 153.722 US fluid ounces in 1 UK gallon (1 imp gal = 153.7215902697 fl oz).

How many UK gallons are in a US fluid ounce?

There are 0.00650527 UK gallons in 1 US fluid ounce (1 fl oz = 0.0065052671 imp gal).

How do I convert UK gallons to US fluid ounces?

Multiply by 153.722, or divide by 0.00650527 if that is easier. Example: 10 imp gal = 1,537.22 fl oz.

What is 10 imp gal in US fluid ounces?

10 imp gal = 1,537.22 fl oz.

What is 100 imp gal in US fluid ounces?

100 imp gal = 15,372.2 fl oz.

How accurate is this UK gallon to US fluid ounce converter?

Yes. The factor comes from the official definitions of both units (NIST Handbook 44, Appendix C, and NIST SP 811 (US customary volume units)). Results are shown to up to 10 decimal places; round them to suit your purpose.

What is an easy way to convert UK gallons to US fluid ounces?

Closer estimate: multiply by 150 (within 2.4%).

How many US fluid ounces is 1 imp gal (one imperial gallon)?

1 imp gal = 153.722 fl oz.

How many UK gallons is a can of soda (12 fl oz)?

12 fl oz = 0.0780632 imp gal.

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Reviewed by

Dr. Muhammad Amjad Khadim PhD Mathematics

Dr. Muhammad Amjad Khadim holds a PhD in Mathematics. He writes and reviews the guides on pakmath.com and checks every formula, conversion factor and worked example against published standards and official guidance before it goes live. Spotted an error? Tell us and it will be corrected.

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First published 28 October 2026 · Last reviewed 5 November 2026