Calculate the BTU output needed to heat your swimming pool. Enter the pool volume and desired temperature rise to determine the right heater size. This calculator helps you choose between gas heaters, electric heat pumps, and solar heating based on your pool's needs.
Enter Your Measurements
Results
Gas Heater Size
150,000
BTU/hr
Heat Pump Size
110,000
BTU/hr
Required BTU/hr (with heat loss)
108,750
BTU/hr
Total BTU to Heat Pool
2,502,000
BTU
Estimated Heat Loss
4,500
BTU/hr
Formula
How to Use This Calculator
How to Use
- 1
Enter the pool volume in gallons.
- 2
Enter the desired temperature rise (the difference between current and target water temperature).
- 3
Enter how many hours you want the heater to bring the pool to temperature.
- 4
Enter the pool surface area for heat loss calculation.
Frequently Asked Questions
Frequently Asked Questions
Gas heater vs heat pump: which is better for pools?
How long does it take to heat a pool?
Does a pool cover help with heating?
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About This Calculator
This calculator uses the formula: Total BTU = Pool Gallons × 8.34 × Temp Rise | Required BTU/hr = Total BTU ÷ Hours + Surface Heat Loss. All calculations follow industry-standard methods. Results are estimates — always verify with a licensed professional for structural or code-compliant work.
Built and maintained by the CalcSmart team. Last updated March 2026.
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