K-Factor Calculator

Q = K × √P — Solve for any variable

What do you want to calculate?

Flow (Q) Volume per time
Pressure (P) Operating pressure
K-Factor (K) Device constant

Result

CALCULATION
Enter values above to calculate

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Common K-Factors

Click a row to use that K-factor in the calculator

Device Type K (L/min/√bar) K (GPM/√PSI)
Standard Sprinkler (15mm) 57 5.6
Standard Sprinkler (20mm) 80 8.0
Large Orifice Sprinkler 115 11.2
Extra Large Orifice 161 11.2
ESFR Sprinkler (K14) 202 14.0
ESFR Sprinkler (K16.8) 242 16.8
ESFR Sprinkler (K25.2) 363 25.2
K-factor conversion: Kmetric ≈ Kimperial × 14.4

Standards Reference

AS 2118.1 — Automatic fire sprinkler systems

NFPA 13 — Standard for the Installation of Sprinkler Systems

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