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

Plumbing

Pipe Flow Rate Calculator

Calculates the volumetric flow rate of water through a pipe in gallons per minute. Use it when sizing pumps, irrigation lines, or plumbing systems where you know pipe diameter and water velocity.

Fill in the required fields to see your result.
Plumbing

Drain Pipe Slope Calculator

Calculates the required vertical drop for a drain pipe based on its length and diameter to ensure proper self-cleaning flow. Use it when roughing in bathroom, kitchen, or floor drains to meet IPC and UPC plumbing code requirements.

Fill in the required fields to see your result.

Key differences

Pipe Flow Rate CalculatorDrain Pipe Slope Calculator
CategoryPlumbingPlumbing
Inputs required22
ResultFlow Rate (GPM)Total Fall Required (inches)
What it doesCalculates the volumetric flow rate of water through a pipe in gallons per minute. Use it when sizing pumps, irrigation lines, or plumbing systems where you know pipe diameter and water velocity.Calculates the required vertical drop for a drain pipe based on its length and diameter to ensure proper self-cleaning flow. Use it when roughing in bathroom, kitchen, or floor drains to meet IPC and UPC plumbing code requirements.