Rectangular Tank Volume Calculator
Capacity and filled volume of a rectangular tank in m³, litres, US and imperial gallons.
Inputs
%
Results
- Filled volume
- 3,240 L
- Filled volume
- 3.24 m³
- Filled volume
- 855.9 US gal
- Filled volume
- 712.7 imp gal
- Full capacity
- 3.6 m³
Formula
Capacity = L × W × H (converted to metres)
Filled = Capacity × Fill% ÷ 100; 1 m³ = 1000 L = 264.172 US gal = 219.969 imp gal
Assumptions & limits
- Use inner dimensions. Wall thickness, fittings and internal structures are ignored.
- Tank is level with vertical walls; fill % is the share of inner height.
Worked example
2 × 1.5 × 1.2 = 3.6 m³ capacity; at 90% → 3.24 m³ = 3,240 L ≈ 855.9 US gal.