An imperial gallon is exactly 4.54609 liters.
Imperial gallons to Quarts Converter — imp gal to qt
Convert Imperial gallon (imp gal) to Quart (qt) using the exact conversion factor (1 imperial gallon = 4.803799702 quart). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Imperial gallons to Quarts converter
Converter
Volume Converter
Convert metric, US customary, imperial, cooking, dry, and industrial volume units.
Context values
Some unit families need one extra value for a physically accurate result.
A US liquid quart is one quarter of a US gallon.
Result = input x 0.00454609 / 0.000946352946.
Volume uses the cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Imperial gallons to Quarts
Imperial gallon and Quart appear side by side at fuel pumps and on beverage labels, since the US measures liquids in gallons while most of the world uses liters. Imperial gallon is typically associated with united Kingdom, Canada (some contexts), and other Commonwealth countries, while Quart is typically associated with united States (cooking, dairy, motor oil packaging).
Formula
quarts = imperial gallons × 4.80379970202
This factor comes from each unit's defined relationship to the category's base unit: 1 imperial gallon equals 0.00454609 base units, and 1 quart equals 0.000946352946 base units, so dividing one by the other gives the direct imperial gallon-to-quart factor of 4.80379970202.
Simple example
1 imp gal × 4.803799702 = 4.803799702 qt
1 imperial gallon = 4.803799702 quarts.
Real-world example
10 imp gal × 4.803799702 = 48.03799702 qt
10 imperial gallons = 48.03799702 quarts.
Conversion table
| Imperial gallon (imp gal) | Quart (qt) |
|---|---|
| 1 imp gal | 4.803799702 qt |
| 5 imp gal | 24.01899851 qt |
| 10 imp gal | 48.03799702 qt |
| 25 imp gal | 120.0949926 qt |
| 50 imp gal | 240.1899851 qt |
| 100 imp gal | 480.3799702 qt |
Reverse conversion: Quart to Imperial gallon
4.803799702 qt × 0.2081685462 = 1 imp gal
4.803799702 quarts = 1 imperial gallons.
imperial gallons = quarts × 0.208168546157
For a page dedicated to this direction, see Quart to Imperial gallon.
Imperial gallon vs. Quart
| Aspect | Imperial gallon | Quart |
|---|---|---|
| Family | UK/imperial customary unit | US customary unit |
| Typical use | UK fuel and beverage measurement (historically; UK now primarily uses liters for retail) | US recipe measurement (larger liquid volumes) |
| Where it's used | United Kingdom, Canada (some contexts), and other Commonwealth countries | United States (cooking, dairy, motor oil packaging) |
Understanding the Imperial gallon
Imperial gallon (imp gal) measures volume. The imperial gallon is defined as exactly 4.54609 liters, about 20% larger than the US gallon. It is classified as a UK/imperial customary unit.
Where it's used: United Kingdom, Canada (some contexts), and other Commonwealth countries
Imperial gallon vs. US gallon. Britain's 1824 Weights and Measures Act defined a new gallon based on 10 pounds of water, replacing the old wine gallon the US had already adopted — leaving the US (3.785 L) and imperial (4.546 L) gallons about 20% apart today.
Uses of the Imperial gallon today
- UK fuel and beverage measurement (historically; UK now primarily uses liters for retail)
- Commonwealth country liquid measurement in some contexts
History of the Imperial gallon
The imperial gallon was created by Britain's Weights and Measures Act of 1824, defined as the volume of 10 pounds of water, replacing several inconsistent older English gallon definitions (wine gallon, ale gallon, corn gallon) with one standard.
Historical origin. Imperial gallon was not the invention of a single named person; it developed through the process described above.
Understanding the Quart
Quart (qt) measures volume. The US liquid quart is exactly one-quarter of a US gallon: 0.946352946 liters. It is classified as a US customary unit.
Where it's used: United States (cooking, dairy, motor oil packaging)
Uses of the Quart today
- US recipe measurement (larger liquid volumes)
- US motor oil and automotive fluid packaging
- US dairy and beverage packaging (quart containers)
History of the Quart
The quart ('quarter' of a gallon) follows the same English wine-gallon lineage as the US gallon, retained by the US after England moved to a different imperial standard in 1824.
Historical origin. Quart was not the invention of a single named person; it developed through the process described above.
Imperial gallon — sources
- UK Weights and Measures Act 1824 — Establishes the imperial gallon definition.
Quart — sources
- NIST Handbook 44, Appendix C — General tables of units including the US quart definition.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many quarts are in 1 imperial gallon?
1 imperial gallon equals 4.803799702 quarts, using the exact defined conversion factor rather than an estimate.
How do I convert imperial gallon to quart?
Multiply the imperial gallon value by 4.803799702. The converter above does this instantly to whatever precision you set.
How do I convert quart back to imperial gallon?
Use the reverse factor: 1 quart equals 0.2081685462 imperial gallons. You can also use the swap control in the converter above to flip the direction instantly.
What is a imperial gallon?
Imperial gallon (imp gal) measures volume. The imperial gallon is defined as exactly 4.54609 liters, about 20% larger than the US gallon. It is classified as a UK/imperial customary unit.
What is a quart?
Quart (qt) measures volume. The US liquid quart is exactly one-quarter of a US gallon: 0.946352946 liters. It is classified as a US customary unit.
Is the imperial gallon to quart conversion exact?
Yes. The US liquid quart is exactly one-quarter of a US gallon: 0.946352946 liters. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between imperial gallon vs. us gallon?
Britain's 1824 Weights and Measures Act defined a new gallon based on 10 pounds of water, replacing the old wine gallon the US had already adopted — leaving the US (3.785 L) and imperial (4.546 L) gallons about 20% apart today.
Where is the imperial gallon still used today?
United Kingdom, Canada (some contexts), and other Commonwealth countries