everyday calculator
Aquarium Volume Calculator
Estimate ideal internal aquarium capacity from disclosed geometric dimensions.
Aquarium Volume Calculator
Result
Enter dimensions and calculate.
Formula version 1.0.0
How to use this calculator
- Choose rectangular or cylindrical aquarium.
- Choose centimetres or inches.
- Enter internal dimensions; cylindrical width means internal diameter.
- Calculate and read litres and US gallons.
Symbols and units
| Symbol | Meaning | Unit or domain |
|---|---|---|
l,w,h | Internal length, width, height | cm or in |
d | Internal cylinder diameter | cm or in |
L | Geometric capacity | litres |
US gal | US liquid gallons | 3.785411784 L |
Checked examples
Rectangular tank
Inputs: 100×40×50 cm
Calculation: 1×0.4×0.5 m³×1000
Result: 200 L
Ideal internal geometric capacity.
Check: geometry-task86.test.ts
12-inch cube
Inputs: 12×12×12 in
Calculation: 12³ cubic inches converted
Result: about 28.32 L
Before displacement or headspace.
Check: geometry-task86.test.ts
Assumptions, rounding, and limits
- Use internal measurements.
- Real usable water is lower because of glass geometry, substrate, décor, equipment, and headspace.
- US gallons are used, not imperial gallons.
- This is capacity math, not stocking or animal-care advice.
Frequently asked questions
Why use internal dimensions?
External dimensions include wall thickness and overstate capacity.
Is calculated volume usable water?
Usually not; displacement and unfilled space reduce it.
Does this recommend fish stocking?
No. It only estimates geometric capacity.
Sources and review
- BIPM: SI Brochure — Metre and litre definitions
- NIST: NIST Guide to SI conversion factors — Inch and US gallon conversion factors
- Formula version
- aquarium.volume@1.0.0
- Formula review
- Equatara formula review
- Editorial review
- Equatara editorial review
- Last verified
- 2026-10-25
- Applicability
- Global capacity estimate; no animal-care guidance.
- Next review
- On material change or by 2028-10-25.
Related calculators
Found a problem?
Report a formula, result, example, source, or accessibility issue through the calculator correction process. Do not include sensitive input values.