Nirmion
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WATER / RECTANGULAR OR CYLINDRICAL

Water Tank Volume Calculator

Calculate usable and full water capacity for rectangular or cylindrical tanks from metre dimensions and an entered fill level.

  • 01 Calculated in this tab
  • 02 Values stay in this browser tab
  • 03 Use boundary

Conversion input

Known value

Filter by unit name, symbol, or code. Your current selections remain available.

Tank geometry

Fill assumption

Preparing the calculator...

Use boundary

Calculation path

The selected geometric volume in cubic metres is converted at 1,000 litres per cubic metre and scaled by fill level.

Calculation path

Volume = pi x (diameter / 2)^2 x height x fill fraction.

What you provide

What you provide

  • Tank shape: Choose how the three dimension fields are interpreted.
  • Dimension A: Cylinder diameter or rectangular length, in metres.
  • Dimension B: Cylinder height or rectangular width, in metres.
  • Dimension C: Rectangular height; ignored for a cylinder.
  • Fill percentage: Share of full geometric capacity currently usable.

What you receive

What you receive

  • Usable water volume
  • Full geometric capacity
  • Cubic-metre and fill-level context

Use boundary

Choose the maximum decimal places shown. This does not increase source accuracy.

Internal dimensions, freeboard, wall thickness, fittings, dead storage, tilt, and irregular shapes can reduce usable capacity.

Planning and fitness outputs are estimates. Confirm measurements, product specifications, site conditions, health context, and professional requirements before making purchasing, training, medication, or care decisions.

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