poolchemistrycalc

Pool volume calculator in litres

Your pool holds

48,000L 12,700gal

A rectangle of 32.0 m², 150.0 cm of average water depth. Depth basis: shallow and deep end averaged

Litres are worked out from the metres and centimetres you entered. The gallons figure beside them is the same water in US gallons.

The figures above are worked for the shape this page was published with. Pick another one and they are worked again as you type — with JavaScript off, the chips only show which measurements that shape needs.

Section through a rectangle pool from the water surface to the floor: the shallow end 120 cm, the deep end 180 cm, and the 150.0 cm average depth the 48,000 L figure is computed from. water surface 8 m × 4 m 150.0 cm average litres use this 120 cm 180 cm deep end not the depth used 48,000 L 12,700 gal

Your pool

metres, the long side
metres
centimetres of water, not wall height
centimetres of water
metres, across the middle
centimetres, surface to floor
metres, the long side
metres
centimetres, surface to floor
square metres
centimetres, surface to floor

Your readings

in ppm
in pH
in ppm
in ppm
in ppm

The answer, the drawings, every reading and every table on this page are worked for the values in these fields, and worked again as you type. The questions further down are answered for the example this page was published with.

Each reading against its band

Your readings

At 48,000 L

What to add

Every product whose own label states a strength and moves a reading that is outside its band, at the volume above. The second line is the same quantity in metric.
Fixes Product Add
Free chlorine
+2.5 ppm
HASA CHLOR
sodium hypochlorite
960 mL
1.01 qt
Free chlorine
+2.5 ppm
Multi-Chlor
sodium hypochlorite
960 mL
1.01 qt
Free chlorine
+2.5 ppm
Pool Shock Calcium Hypochlorite 65%
calcium hypochlorite
185 g
6.5 oz
pH
−0.5 pH
HASA Dry Acid
sodium bisulfate
720 g
1.59 lb
pH
−0.5 pH
HASA Muriatic Acid
hydrochloric acid
no quantity — see the label
Total alkalinity
+40 ppm
HASA Alkalinity Up
sodium bicarbonate
3.22 kg
7.11 lb
Calcium hardness
+120 ppm
HASA Calcium Chloride
calcium chloride
8.19 kg
18.05 lb
Stabiliser
+20 ppm
HASA Pool Conditioner
cyanuric acid
980 g
2.16 lb

Order matters. Alkalinity buffers pH, so set the alkalinity first — the pH you correct before it will move again when the alkalinity does. Add one thing at a time, let the pump turn the water over, and test again before you add the next. No product page we have read states how long to wait, so we do not put a number on it.

Fix a reading

Gallons, from a pool measured in feet

What people ask

How do I calculate a pool's volume in litres?
Surface area in square metres times average depth in centimetres, divided by 100, times 1,000. For this rectangle of 32.0 m²: an average depth of 150.0 cm, which gives 48,000 L.
How many litres does a 8.0 m pool hold?
48,000 L at 4.0 m wide and an average depth of 150.0 cm, which is 12,700 gal in US gallons.

Updated September 2026

Pool and spa rules are adopted and amended state by state, and most of the ranges here are written for public pools. Confirm every figure against the code your jurisdiction has adopted and against your own product label.

Sources and dates

Ranges are quoted from the code named beside them, product strengths from the manufacturer's own product page, each retrieved on the date shown.