Pool Volume Calculator
Knowing your pool volume in gallons is the starting point for dosing chemicals and estimating the cost to fill it. Enter the dimensions to get the capacity in gallons — and roughly how long a garden hose takes to fill it.
Your numbers
Result
- Volumecu ft
- 2,250
- Time to fillhours
- 31.17
| Item | Value |
|---|---|
| Volume | 2250.0 cu ft |
| Capacity | 16831 gallons |
| Time to fill | 31.2 h |
How to calculate pool gallons
Rectangular pool: length × width × average depth (in feet) gives cubic feet; multiply by 7.48 for gallons. A 30 × 15 × 5 ft pool is 2,250 cu ft ≈ 16,830 gallons. Round pool: π × radius² × depth × 7.48. For a sloped bottom, use the average depth between the shallow and deep ends.
Volume drives your chemicals
Chlorine, shock, algaecide and pH adjusters are all dosed per gallon (or per 10,000 gallons), so getting the volume right keeps the water balanced and avoids wasting product. Aim to keep pH between 7.2 and 7.6 and free chlorine in range for the chemicals to work.
Time and cost to fill
Fill time is gallons ÷ fill rate. A garden hose delivers roughly 9 gallons per minute (~540 gal/h), so a 16,800-gallon pool takes about 31 hours. That is a lot of metered water — factor the cost into your budget and check for local restrictions during droughts.
Frequently asked questions
Sources
- Volume geometry (prism and cylinder); 1 cu ft = 7.48 US gallons
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