Tool
Aquarium Volume Unit Converter
Type a value in any field and the other five update instantly. Useful for reading European tank specs in litres, checking imperial gallon figures from UK sources, or turning a cubic-inch calculation into gallons.
Values are rounded for display; conversions use exact factors.
Conversion reference
| US gal | Liters | Imp gal | in³ | ft³ |
|---|---|---|---|---|
| 1 | 3.8 | 0.8 | 231 | 0.13 |
| 5 | 18.9 | 4.2 | 1,155 | 0.67 |
| 10 | 37.9 | 8.3 | 2,310 | 1.34 |
| 20 | 75.7 | 16.7 | 4,620 | 2.67 |
| 29 | 109.8 | 24.1 | 6,699 | 3.88 |
| 40 | 151.4 | 33.3 | 9,240 | 5.35 |
| 55 | 208.2 | 45.8 | 12,705 | 7.35 |
| 75 | 283.9 | 62.5 | 17,325 | 10.03 |
| 90 | 340.7 | 74.9 | 20,790 | 12.03 |
| 125 | 473.2 | 104.1 | 28,875 | 16.71 |
| 180 | 681.4 | 149.9 | 41,580 | 24.06 |
| 250 | 946.4 | 208.2 | 57,750 | 33.42 |
Why units matter for aquarium volume
Medication and fertiliser instructions are written per gallon or per litre, and mixing the two is the fastest way to overdose a tank by a factor of nearly four. Filter and heater ratings on international products are usually in litres, while most North American tank sizes are in US gallons. Keep one unit for your tank record and convert everything else to it.
Frequently asked questions
3.785 litres. Multiply gallons by 3.785 for litres, or divide litres by 3.785 for gallons.
An imperial gallon is 4.546 litres, about 20% larger than a US gallon. This converter handles both.
Divide by 231. A tank of 12,000 cubic inches is 51.9 US gallons.
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