Plumbing Calculators
Pipe sizing, drainage slope, water heater sizing, gas pipe, and fixture unit calculations. Every result is IPC and IFGC-referenced and ready for the field.
Tools built for the trade
From quick pipe-sizing lookups to IPC-referenced drainage slope compliance. Free to use, no account required to view.
Pipe Sizing Calculator
Look up minimum supply pipe diameter for a given fixture unit load per IPC Table E103.3.
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Water Heater Sizing
Size a residential water heater by number of bedrooms and bathrooms.
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Drainage Slope Calculator
Calculate drain line slope and verify IPC compliance (1/8 in/ft minimum).
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Gas Pipe Sizing
Look up minimum gas pipe diameter for a BTU load and run length per IFGC tables.
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Fixture Unit Calculator
Sum drainage fixture units (DFU) for plumbing system sizing.
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