Convert Imperial gallons to Cubic metres
1 imperial gallon is 0.004546 m³. One imperial gallon is exactly 0.00454609 cubic metres.
One imperial gallon is 0.00454609 cubic metres. To convert imperial gallons to cubic metres, multiply by 0.00454609; to go the other way, divide by 0.00454609 or multiply by 219.96925. The factor is exact rather than rounded: it follows from NIST Handbook 130.
Factor checked against the defining standard · How we check
- Imperial gallons × 0.00454609
1 * 0.00454610.005 m³
1 imperial gallon in every volume unit
| Unit | Value | Exact factor |
|---|---|---|
| US teaspoons | 922.3295428 tsp | × 922.329542788 |
| US tablespoons | 307.4431809 tbsp | × 307.443180929 |
| US fluid ounces | 153.7215905 fl oz | × 153.721590465 |
| US cups | 19.21519881 cup | × 19.2151988081 |
| US pints | 9.607599404 pt | × 9.60759940404 |
| US quarts | 4.803799702 qt | × 4.80379970202 |
| US gallons | 1.200949926 gal | × 1.2009499255 |
| milliliters | 4,546.09 ml | × 4,546.09 |
| liters | 4.54609 L | × 4.54609 |
| imperial gallons (as entered) | 1 gal (UK) | — |
| imperial quarts | 4 qt (UK) | × 4 |
| imperial pints | 8 pt (UK) | × 8 |
| imperial fluid ounces | 160 fl oz (UK) | × 160 |
| imperial gills | 32 gi (UK) | × 32 |
| cubic millimetres | 4,546,090 mm³ | × 4,546,090 |
| cubic centimetres | 4,546.09 cm³ | × 4,546.09 |
| cubic inches | 277.4194328 in³ | × 277.419432792 |
| cubic feet | 0.1605436532 ft³ | × 0.160543653236 |
| cubic yards | 0.005946061231 yd³ | × 0.00594606123096 |
| cubic metres | 0.00454609 m³ | × 0.00454609 |
Factors are entered by hand from NIST Handbook 130 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert imperial gallons to cubic metres? The converter and the working
- 1.Take the measurement in imperial gallons.
- 2.Multiply by 0.00454609 — that is how many cubic metres fit in one imperial gallon.
- 3.To go back the other way, divide by 0.00454609, or multiply by 219.96925.
Worked example: 25 imperial gallons to cubic metres
- Formula
- gal (UK) × 0.00454609 = m³
- Arithmetic
- 25 × 0.00454609 = 0.11 m³
- Answer
- 25 gal (UK) = 0.11 m³
The factor is exact, so this figure is exact too — only the display is rounded.
Imperial gallons to cubic metres conversion table
| Imperial gallons | Cubic metres |
|---|---|
| 1 gal (UK) | 0.004546 m³ |
| 2 gal (UK) | 0.01 m³ |
| 3 gal (UK) | 0.01 m³ |
| 4 gal (UK) | 0.02 m³ |
| 5 gal (UK) | 0.02 m³ |
| 6 gal (UK) | 0.03 m³ |
| 7 gal (UK) | 0.03 m³ |
| 8 gal (UK) | 0.04 m³ |
| 9 gal (UK) | 0.04 m³ |
| 10 gal (UK) | 0.05 m³ |
| 12 gal (UK) | 0.05 m³ |
| 15 gal (UK) | 0.07 m³ |
| 20 gal (UK) | 0.09 m³ |
| 25 gal (UK) | 0.11 m³ |
| 50 gal (UK) | 0.23 m³ |
| 100 gal (UK) | 0.45 m³ |
| 200 gal (UK) | 0.91 m³ |
| 300 gal (UK) | 1.36 m³ |
| 500 gal (UK) | 2.27 m³ |
| 1000 gal (UK) | 4.55 m³ |
| 2000 gal (UK) | 9.09 m³ |
| 5000 gal (UK) | 22.73 m³ |
| 10000 gal (UK) | 45.46 m³ |
What is an imperial gallon?
Exactly 4.54609 liters since 1985, and the reason UK and US fuel economy figures cannot be compared: it is 20% larger than the US gallon, so 40 mpg in Britain is about 33 mpg in America on the same car.
What is a cubic metre?
Exactly a thousand litres, by the definition of the litre. The SI unit of volume, and how the rest of the world orders concrete.
How many cubic metres are in an imperial gallon?
One imperial gallon is 0.00454609 cubic metres, exactly. Going the other way, one cubic metre is 219.96925 imperial gallons. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every volume unit here
The whole group — 20 units with their symbols and the size of each one in liters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to an imperial gallon.
Cite this page
- APA
- Rule Calculator. (2026). Convert Imperial gallons to cubic metres. Rule Calculator. https://rulecalculators.com/convert/imperial-gallon-to-cubic-meter
- MLA
- "Convert Imperial gallons to cubic metres." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/imperial-gallon-to-cubic-meter.
- Chicago
- Rule Calculator. "Convert Imperial gallons to cubic metres." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/imperial-gallon-to-cubic-meter.
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Questions people actually ask
- How many cubic metres are in an imperial gallon?
- 0.00454609. Exactly a thousand litres, by the definition of the litre. The SI unit of volume, and how the rest of the world orders concrete.
- How do I convert cubic metres back to imperial gallons?
- Divide by 0.00454609, or multiply by 219.96925 — they are the same operation.
Other volume conversions
Cubic metres to imperial gallons — the same conversion the other way.