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Pipe Flow Calculator

Determine pressure drop in circular pipes using the Darcy-Weisbach equation. Use this when designing water supply lines, HVAC ducts, or industrial piping systems to ensure adequate flow.

Pipe Diameter (m)

Pipe Length (m)

Pipe Material

Flow Velocity (m/s)

Kinematic Viscosity (m²/s)

Fill in the required fields to see your result.

Fluid Mechanics

Pipe Sizing Calculator

Find the minimum required pipe diameter to keep fluid velocity within safe limits for a given flow rate. Use this when selecting pipe sizes for new installations or checking whether existing pipes can handle increased flow.

Flow Rate (L/min)

Maximum Velocity (m/s)

Safety Factor

Fill in the required fields to see your result.

Key differences

	Pipe Flow Calculator	Pipe Sizing Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	5	3
Result	Pressure Drop (Pa)	Minimum Pipe Diameter (mm)
What it does	Determine pressure drop in circular pipes using the Darcy-Weisbach equation. Use this when designing water supply lines, HVAC ducts, or industrial piping systems to ensure adequate flow.	Find the minimum required pipe diameter to keep fluid velocity within safe limits for a given flow rate. Use this when selecting pipe sizes for new installations or checking whether existing pipes can handle increased flow.