Sprinkler K-Factor Solver

Solve Q = K x sqrt(P) for flow, pressure, or K-factor.

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Example

You enter

You get

Details, formula, and sources

Per NFPA 13; complements the design-density calculation.

Q = K * sqrt(P), solved for flow Q (gpm), pressure P (psi), or the nominal nameplate K-factor.

NFPA 13 sprinkler discharge relation Q = K*sqrt(P), by name.

Free read-only at nfpa.org/freeaccess; NFPA 13 governs the design.

Estimate. AHJ and licensed fire protection engineer govern.

Field names used by the API: solve_for, k_factor, pressure_psi, flow_gpm

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