Pool Volume Calculator
Calculate the water volume of a rectangular, round or oval pool in gallons and litres.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
About this calculator
Pool turnover time uses the pump flow rate you enter. Volume is estimated from the selected shape and average depth; kidney pools use an approximate 0.72 factor. Actual contours and pump flow can vary.
Worked example
calculated with the default values below
Pool shape Rectangular · Length or diameter 30 ft · Width 15 ft · Shallow end depth 3 ft · Deep end depth 6 ft · Pump flow rate 85 gpm Water volume 15,148 gal · Water volume 57,342 L · Average depth 4.50 ft · Volume 2,025 cu ft · Turnover hours at entered flow 3.0 h
Method and assumptions
V = L × W × d × k; d = (d_s + d_p) ÷ 2; gal = V × 7.48052 Uses selected shape and average depth; kidney pools use a 0.72 approximation. Turnover hours = estimated gallons / entered pump flow (gallons per minute) / 60. The pump flow is user-supplied and actual pool contours vary. Pool turnover time uses the pump flow rate you enter. Volume is estimated from the selected shape and average depth; kidney pools use an approximate 0.72 factor. Actual contours and pump flow can vary. Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
Data sources
Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
Disclaimer
These calculators provide planning estimates only. Building codes, wiring regulations and safety requirements differ by country and change over time, and nothing here replaces a licensed professional or a permit. For structural, electrical or gas work, follow local code and have the installation inspected.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
V = L × W × d × k; d = (d_s + d_p) ÷ 2; gal = V × 7.48052
- V
- Volume (ft³)
- L
- Length (ft)
- W
- Width (ft)
- d
- Average depth (ft)
- k
- Shape factor
- d_s, d_p
- Shallow-end and deep-end depths (ft)
Uses selected shape and average depth; kidney pools use a 0.72 approximation. Turnover hours = estimated gallons / entered pump flow (gallons per minute) / 60. The pump flow is user-supplied and actual pool contours vary.
Frequently asked questions
How is turnover time estimated?
Turnover time is estimated by dividing the calculated pool volume by the pump flow rate you enter, then converting minutes to hours. Use the pump’s actual flow under your plumbing and filter conditions; the nameplate maximum may differ.
Why does a kidney-shaped pool use a 0.72 area factor?
The shape select changes the volume formula: round and oval use pi, rectangle is length times width, but kidney multiplies length times width times depth by 0.72 to approximate its pinched shape. At 30x15 feet with 3 and 6 foot ends the average depth is 4.5, a rectangle would be 2,025 cu ft, and the kidney gives 0.72*2,025 ≈ 1,458 cu ft, or about 10,900 gallons at 7.48052 per cu ft. The turnover time then divides that by 85 gpm.
Which inputs and limits apply to Pool Volume Calculator?
Use the units shown beside each field. These are form limits, not recommended settings. Length or diameter: 1–300 ft; Width: 1–300 ft; Shallow end depth: 0.5–12 ft; Deep end depth: 0.5–20 ft; Pump flow rate: 1–1,000 gpm V = L × W × d × k; d = (d_s + d_p) ÷ 2; gal = V × 7.48052 Uses selected shape and average depth; kidney pools use a 0.72 approximation. Turnover hours = estimated gallons / entered pump flow (gallons per minute) / 60. The pump flow is user-supplied and actual pool contours vary. Pool turnover time uses the pump flow rate you enter. Volume is estimated from the selected shape and average depth; kidney pools use an approximate 0.72 factor. Actual contours and pump flow can vary. Use the cited guidance and your own measurements, bills or product specifications to choose inputs. Sample defaults are not current local data.
What is a complete worked example for Pool shape = Rectangular; Length or diameter = 30 ft?
Inputs: Pool shape = Rectangular; Length or diameter = 30 ft; Width = 15 ft; Shallow end depth = 3 ft; Deep end depth = 6 ft; Pump flow rate = 85 gpm. Calculation: V = L × W × d × k; d = (d_s + d_p) ÷ 2; gal = V × 7.48052. Results: Water volume = 15,148 gal; Water volume = 57,342 L; Average depth = 4.50 ft; Volume = 2,025 cu ft; Turnover hours at entered flow = 3.0 h.