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Weir Flow Calculator

Calculate volumetric flow rate over rectangular, triangular, or trapezoidal weirs from the head of water above the weir crest. Used in irrigation canals, wastewater treatment, and stream gauging.

Weir Width/Length (m)

Head Over Weir (m)

Weir Type

Discharge Coefficient

End Contractions

Fill in the required fields to see your result.

Fluid Mechanics

Orifice Flow Calculator

Calculate volumetric flow rate through an orifice plate or sharp-edged opening given pressure drop and fluid properties. Widely used for flow metering in industrial pipelines and process plants.

Orifice Diameter (m)

Pressure Difference (Pa)

Fluid Density (kg/m³)

Orifice Type

Beta Ratio (d/D)

Fill in the required fields to see your result.

Key differences

	Weir Flow Calculator	Orifice Flow Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	5	5
Result	Flow Rate (m³/s)	Flow Rate (m³/s)
What it does	Calculate volumetric flow rate over rectangular, triangular, or trapezoidal weirs from the head of water above the weir crest. Used in irrigation canals, wastewater treatment, and stream gauging.	Calculate volumetric flow rate through an orifice plate or sharp-edged opening given pressure drop and fluid properties. Widely used for flow metering in industrial pipelines and process plants.