Valve & Fluid-Control Calculators
Free, practical tools for sizing and checking a fluid system — work out a valve Cv, the pressure drop it imposes, the velocity in a pipe, the valve size a duty needs, flow-unit conversions, and the Reynolds number that sets the flow regime.
Valve Cv Calculator
Turn a flow rate, pressure drop, and specific gravity into the flow coefficient a valve needs — Cv = Q×√(SG/ΔP), with the metric Kv alongside it.
Valve Pressure Drop Calculator
Estimate the pressure a valve consumes from flow, its Cv, and specific gravity — ΔP = SG×(Q/Cv)², reported in psi and bar.
Flow Velocity Calculator
Get fluid velocity in a pipe from volumetric flow and inside diameter (v = Q/A), in gpm/L·min and inch/mm, with a high-velocity warning.
Valve Sizing Calculator
From required flow, allowable pressure drop, and specific gravity, get the required Cv and the next-larger nominal rated Cv with its headroom margin.
Flow Rate Unit Converter
Convert a volumetric flow between US GPM, litres per minute, cubic metres per hour, and CFM — enter one value and read all four.
Reynolds Number Calculator
Compute the Reynolds number from velocity, inside diameter, and kinematic viscosity (Re = v·d/ν) and classify laminar, transitional, or turbulent flow.