This converter turns imperial gallons into cubic feet instantly, using the exact factor 1 imperial gallon = 0.1605436532 cubic feet. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
Exactly 4.54609 litres, about 20% larger than the US gallon. The volume of a one-foot cube — used for shipping, refrigerators and natural gas.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
imperial gallons- The amount you are converting, measured in imperial gallons
0.1605436532- The exact number of cubic feet in one imperial gallon
cubic feet- The converted result
How it works, step by step
- Enter the number of imperial gallons you want to convert.
- The value is multiplied by 0.1605436532, the exact conversion factor.
- The result is displayed in cubic feet, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 imperial gallons
Multiply 5 by 0.16054365. That gives 0.802718 cubic feet. A quick sanity check: one imperial gallon is smaller than one cubic foot, so the number should get smaller — and it does.
Converting 72 imperial gallons
72 × 0.16054365 = 11.5591 cubic feet. Working backwards, 11.5591 ÷ 0.16054365 returns 72 imperial gallons, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many cubic feet are in one imperial gallon?
Exactly 0.1605436532. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert imperial gallons to cubic feet?
Cubic Feet = imperial gallons × 0.1605436532. To reverse it, divide instead: imperial gallons = cubic feet ÷ 0.1605436532, which is the same as multiplying by 6.228835459.
Is the imperial gallon bigger than the cubic foot?
No. One imperial gallon is only 0.160544 of a cubic foot, so the cubic foot is the larger unit.
Why does my answer differ slightly from other imperial-gallons to cubic-feet converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a imperial gallon?
Exactly 4.54609 litres, about 20% larger than the US gallon.
What is a cubic foot?
The volume of a one-foot cube — used for shipping, refrigerators and natural gas.
Imperial Gallons to cubic feet reference table
| Imperial Gallons | Cubic Feet |
|---|---|
| 0.5 gal | 0.080272 ft³ |
| 1 gal | 0.160544 ft³ |
| 2 gal | 0.321087 ft³ |
| 3 gal | 0.481631 ft³ |
| 5 gal | 0.802718 ft³ |
| 10 gal | 1.6054 ft³ |
| 15 gal | 2.4082 ft³ |
| 20 gal | 3.2109 ft³ |
| 25 gal | 4.0136 ft³ |
| 50 gal | 8.0272 ft³ |
| 75 gal | 12.0408 ft³ |
| 100 gal | 16.0544 ft³ |
| 250 gal | 40.1359 ft³ |
| 500 gal | 80.2718 ft³ |
| 1000 gal | 160.5437 ft³ |
Exact factor: 1 imperial gallon = 0.1605436532 cubic feet. Values rounded for display.