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Pipe Pressure Drop Calculator

Calculate frictional pressure drop in a pipe using the Darcy-Weisbach equation, given friction factor, length, diameter, and fluid velocity. Use it for pump sizing, HVAC duct design, and fluid distribution system layout.

Friction Factor

Pipe Length (m)

Pipe Diameter (m)

Flow Velocity (m/s)

Chemical Engineering

Reynolds Number Calculator

Compute the Reynolds number Re = ρvD/μ — the dimensionless ratio of inertial to viscous forces in a flowing fluid. The single most important number for predicting laminar vs turbulent flow in pipes, channels, and around objects.

Fluid Density (kg/m³)

Flow Velocity (m/s)

Pipe Diameter (m)

Dynamic Viscosity (Pa·s)

Key differences

	Pipe Pressure Drop Calculator	Reynolds Number Calculator
Category	Engineering	Chemical Engineering
Inputs required	4	4
Result	Pressure Drop (Pa)	Reynolds Number
What it does	Calculate frictional pressure drop in a pipe using the Darcy-Weisbach equation, given friction factor, length, diameter, and fluid velocity. Use it for pump sizing, HVAC duct design, and fluid distribution system layout.	Compute the Reynolds number Re = ρvD/μ — the dimensionless ratio of inertial to viscous forces in a flowing fluid. The single most important number for predicting laminar vs turbulent flow in pipes, channels, and around objects.