Gallons to Quarts Converter — US & UK Gallons
1 US gallon = 4 US quarts = 8 pints = 16 cups = 128 fl oz. Convert any number of gallons to quarts and other liquid measures for both US and UK Imperial systems.
Gallon type
1 US gallon = 4 US quarts (exact)
- 1
Quarts per gallon
4Exactly 4 quarts per gallon in both US and UK systems by definition. - 2
Total quarts
1 × 4 = 4
How does this calculator work?
1 gallon = 4 quarts exactly in both US and UK systems. US gallon = 3.785 L; UK gallon = 4.546 L. Multiply gallons by 4 for quarts, by 8 for pints, by 128 for US fluid ounces (160 for UK), or by 3.785 / 4.546 for litres.
Formula
How this is calculated
Both US and UK gallon systems divide a gallon into exactly 4 quarts, 8 pints, and 32 gills — these are whole-number ratios by definition, not approximations. The difference is in the absolute size of the gallon: the US liquid gallon is defined as exactly 231 cubic inches (3.785 411 784 litres), while the UK (Imperial) gallon is defined as the volume of 10 pounds of distilled water at 62 °F, equal to exactly 4.546 09 litres. A UK gallon is therefore about 20% larger than a US gallon.
This converter applies the exact factor of 4 for quarts, 8 for pints, and (for US) 16 cups and 128 fluid ounces. It then multiplies by the appropriate litres-per-gallon constant to get metric equivalents. UK fluid ounces per gallon are 160 (20 fl oz per UK pint), while US fluid ounces per gallon are 128 (16 fl oz per US pint) — note that a UK fluid ounce (28.41 mL) is slightly larger than a US fluid ounce (29.57 mL).
The "cup" is a US measure not formally defined in the UK system. US recipes that call for cups assume US fluid ounces (236.6 mL per cup). UK cooks adapting US recipes should note both the cup size difference and the fluid-ounce difference when doubling-down on volume measures.
Frequently asked questions
Exactly 4 quarts per gallon — for both US liquid and UK Imperial gallons. The quart is defined as one-quarter of a gallon in both systems, so the factor of 4 is always exact; only the absolute volume differs between US and UK.
There are 16 US cups in 1 US gallon. One US cup equals 8 US fluid ounces or 236.6 mL. The UK system has no standard "cup" measure; UK cooking typically uses fluid ounces or millilitres directly.
A US liquid gallon = 3.785 L; a UK (Imperial) gallon = 4.546 L — about 20% larger. Consequently, a UK pint (568 mL) is larger than a US pint (473 mL), and a UK fluid ounce (28.41 mL) differs from a US fluid ounce (29.57 mL).
Also known as
TG we-Calculate Editorial Team. (2026). Gallons to Quarts Converter — US & UK Gallons [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/gallons-to-quarts-converter
TG we-Calculate Editorial Team. "Gallons to Quarts Converter — US & UK Gallons." TG we-Calculate. 2026. https://we-calculate.com/calculator/gallons-to-quarts-converter.
TG we-Calculate Editorial Team, "Gallons to Quarts Converter — US & UK Gallons," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/gallons-to-quarts-converter
@misc{wecalculate_gallons_to_quarts_converter, title = {Gallons to Quarts Converter — US & UK Gallons}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/gallons-to-quarts-converter}}, year = {2026}, note = {TG we-Calculate} }
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