Pool Pump Sizing Calculator
Flow needed to turn a pool over in your chosen period, with pipe-velocity check.
Oversized pool pumps waste power cubed — a smaller pump on a longer schedule filters the same water for far less. Suction lines: ≤ 1.8 m/s per APSP-7.
Formula
Pool Pump Sizing Calculator is a free pool pump size for pump engineers, plumbers and plant designers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Pool Pump Sizing Calculator
Flow needed to turn a pool over in your chosen period, with pipe-velocity check. The calculation implements Q = V_pool / T_turnover (ANSI/APSP-7 — suction entrapment avoidance). Oversized pool pumps waste power cubed — a smaller pump on a longer schedule filters the same water for far less. Suction lines: ≤ 1.8 m/s per APSP-7.
How to use Pool Pump Sizing Calculator
- 1Enter Pool volume in m³.
- 2Enter Turnover period in h (Residential 8 h · public 4–6 h per local code).
- 3Enter Suction pipe inner Ø in mm.
- 4Read Required flow, Suction velocity instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Pool Pump Sizing Calculator?
- ✓Implements the standard formula — Q = V_pool / T_turnover
- ✓Reference cited on-page: ANSI/APSP-7 — suction entrapment avoidance
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Built-in engineering verdict flags out-of-range results instantly
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Pool Pump Sizing Calculator use?+
It computes Q = V_pool / T_turnover, per ANSI/APSP-7 — suction entrapment avoidance. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
Oversized pool pumps waste power cubed — a smaller pump on a longer schedule filters the same water for far less. Suction lines: ≤ 1.8 m/s per APSP-7.
Can I use this for pump selection?+
Use it to establish the duty (flow, head, NPSH, power) and then pick a pump whose curve passes through that point near best efficiency. The tool gives you the engineering numbers a supplier will ask for.
Is the Pool Pump Sizing Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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