Swimming Pool Size Calculator

Calculating Pool Volumes

Knowing your pool's volume is vital when making adjustments as all calculations and dose rates are based on it.
There are two easy ways to obtain this information

ASK THE SUPPLIER OF THE POOL or NOTE THE WATER METER READINGS BEFORE AND AFTER FILLING IT

Here is a resource to help you and to convert units into those most useful to you. As mains water is supplied in Britain in cubic metres, start by measuring in metres to obtain an answer in cubic metres. Then use the calculator to convert this figure into litres, imperial gallons or US gallons.

Rectangle & Square pools Enter Dimensions of pool Metres Feet If the pool has a flat bottom, enter the same figure for max and min depth. Metres Feet Inches The Volume of Water Length (L) CU Metres Width (W) Litres Min Depth (D1) IMP Gallons Max Depth (D2) US Gallons Calculate If your pool has a sloping bottom, then take the deepest measurement (D2) and the shallowest (D1). If there are different levels, then you need to do several calculations of area for each depth and add them up at the end.

Circular Enter Dimensions of pool Metres Feet If the pool has a flat bottom, enter the same figure for max and min depth. Metres Feet Inches The Volume of Water Circle Diameter CU Metres Min Depth (D1) Litres Max Depth (D2) IMP Gallons Calculate US Gallons

Ellipses Enter Dimensions of pool Metres Feet If the pool has a flat bottom, enter the same figure for max and min depth. Metres Feet Inches The Volume of Water Major Diameter (A) CU Metres Minor Diameter (B) Litres Min Depth (D1) IMP Gallons Max Depth (D2) US Gallons Calculate If your pool has a sloping bottom, then take the deepest measurement (D2) and the shallowest (D1). If there are different levels, then you need to do several calculations of area for each depth and add them up at the end.

Irregular Shapes For irregular shapes, calculating the area is less accurate. You will need to draw up the pool accurately to scale on graph paper using a square on the paper to represent a meter (or foot) square of pool. When you have finished, count the squares. For partial squares, count anything over half as one and ignore any under a half. When you have the area (A) multiply by depth (D) for the Volume in cubic metres. If you have several depths, break up your area calculation for each depth. Enter Dimensions of pool Metres Feet If the pool has a flat bottom, enter the same figure for max and min depth. Metres Feet Inches The Volume of Water Area (A) CU Metres Depth (D) Litres IMP Litres Calculate US Litres

Conversion into different units

You can easily convert units using the this calculator
(Results are rounded to 4 decimal places)

Cubic Metres to Litres - Multiply by 1000

Cubic Metres to UK Gallons - Multiply by 219.969

UK Gallons to Litres - Multiply by 4.54609

US Gallons to Litres - Multiply by 3.785411

UK Gallons to US Gallons - Multiply by 1.20095

US Gallons to UK Gallons - Multiply by 0.832674