Plumbing Calculators

Pipe sizing, water flow, drainage, and plumbing cost estimators.

Calculate the correct pipe size for water supply lines. Accounts for flow rate, pressure, and fixture units.

Calculate water flow rate through pipes based on diameter, pressure, and length. Uses Hazen-Williams formula.

Size drain and waste pipes by fixture unit load and slope to meet plumbing code requirements.

Estimate septic tank size and drain field area based on bedrooms, daily flow, and soil type.

Size a water heater by peak demand and first-hour rating to find the right tank or tankless unit.

Total water supply fixture units (WSFU) for fixtures to size supply lines and branch piping.