Aquarium Volume Calculator
Enter your tank’s dimensions to get its volume in US gallons and litres, plus the approximate filled weight. For a rectangular tank the formula is length × width × height ÷ 231 (inches → US gallons).
Volume
0 US gal · 0 L
Common aquarium sizes
| Tank | Typical footprint |
|---|---|
| 5 gallon | 16 × 8 × 10 in |
| 10 gallon | 20 × 10 × 12 in |
| 20 gallon high | 24 × 12 × 16 in |
| 20 gallon long | 30 × 12 × 12 in |
| 29 gallon | 30 × 12 × 18 in |
| 40 gallon breeder | 36 × 18 × 16 in |
| 55 gallon | 48 × 13 × 21 in |
| 75 gallon | 48 × 18 × 21 in |
FAQ
- How do you calculate aquarium volume?
- For a rectangular tank: length × width × height (in inches) ÷ 231 = US gallons. AquaGauge does this for you and also handles cube and cylinder shapes.
- How much does a filled aquarium weigh?
- Roughly 10 lb per US gallon once you add water, substrate and rock — so a 55-gallon tank can exceed 600 lb. Always check your stand and floor.