Skip to content
Calculator Collection

Compare calculators

Both calculators run independently β€” change the inputs on either side to compare results.

Fluid Mechanics

Manning's Roughness Flow Calculator

Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.

Fill in the required fields to see your result.
Fluid Mechanics

Hazen-Williams Flow Calculator

Estimate water flow velocity and discharge in a pressurized pipe using the empirical Hazen-Williams equation. Useful for water distribution system design and quick hydraulic calculations on municipal water mains.

Fill in the required fields to see your result.

Key differences

Manning's Roughness Flow CalculatorHazen-Williams Flow Calculator
CategoryFluid MechanicsFluid Mechanics
Inputs required33
ResultFlow Velocity (m/s)Flow Rate (mΒ³/s)
What it doesEstimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient. Useful for stormwater design, culvert sizing, channel design, and natural-stream hydraulic analysis.Estimate water flow velocity and discharge in a pressurized pipe using the empirical Hazen-Williams equation. Useful for water distribution system design and quick hydraulic calculations on municipal water mains.