Fan Brake Horsepower Calculator

Air horsepower is CFM × pressure ÷ 6356; divide by efficiency for shaft power.

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Formula

BHP = CFM × TSP ÷ (6356 × η)

Example calculation

2,000 CFM at 1.0 inWC, 60% → 0.52 bhp.

Practical HVAC use

Motor selection and energy estimates.

Common mistakes

Using static pressure where total pressure is specified.

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Educational tool. Results are estimates from the stated formulas; always confirm with manufacturer data and the code adopted in your jurisdiction. All calculators