Plumbing & HVAC calculators

Pipe and tank volume, pool gallons, pump flow, duct CFM and room BTU — capacities and flows in US or metric units. Every one works in feet and inches or in metric — flip the switch at the top and the numbers you have typed convert with it.

• Pipe volume gallons or litres a pipe holds
• Pipe offset travel and cut length for 45°, 22½° and other fittings
• Gutter & downspouts roof runoff and how many downspouts
• Tank volume full or part-full cylinder capacity
• Pump GPM flow rate from a bucket test or pipe
• Duct CFM airflow from area & velocity or ACH
• Duct size round and rectangular size from your friction rate or velocity
• BTU / room heat heating or cooling load from your own factors
• Pool volume gallons or litres in a pool or pond

Which one do I need?

Capacities and flows in US gallons or litres, gpm or L/min, CFM or L/s — whichever your gauges read.

• Water held in a run of pipe? Pipe volume calculator →
• Gallons in a tank, full or part-full? Tank volume calculator →
• Gallons or litres in a pool? Pool volume calculator →
• Sizing a heater or an air conditioner? BTU calculator →
• Airflow in a duct? Duct CFM calculator →
• What size duct for the airflow? Duct size calculator →

The other drawers

• Concreto y mampostería
• Estructura y carpintería
• Terreno y jardinería
• Acabados e interiores
• Medición y trazo
• Electricidad
• Taller y equipo
• Conversiones
• Todas las herramientas