What Is a Pressure Head Calculator?
This calculator converts a pressure reading — in PSI, kPa or bar — into the equivalent "head" of fluid, expressed as the height of a column of liquid that would produce that same pressure at its base. Head is the language pumps, tanks and plumbing systems are usually sized in, while gauges usually read in pressure units, so converting between the two is a routine step for plumbers, HVAC technicians and irrigation designers.
The conversion is built on a simple physical fact: water weighs 62.4 pounds per cubic foot, so a column of water exactly 2.31 feet tall pushes down with 1 pound per square inch of pressure at its base. Every other result on this page is derived from that one constant.
How to Read Your Results
Head of Water (Feet)
This is the main result: the height of a water column that would generate the pressure you entered, adjusted for the fluid's specific gravity. It's the number most pump curves and tank-fill charts are labeled in.
Head (Meters) and Head (Inches)
The same head value converted to metric and to inches, useful when comparing against equipment specified in different unit systems.
Pressure in PSI
Your entered pressure converted to PSI, shown so you can double-check the unit conversion step before trusting the head result.
Specific Gravity
Specific gravity compares a fluid's density to water. Water is 1.0 by definition; glycol mixes and light oils typically run higher (roughly 1.03–1.1), which slightly shortens the head needed for a given pressure, while some solvents run lower and need a taller column.
Real-World Example
A residential well pump reads 50 PSI at the pressure switch and the fluid is plain water (specific gravity 1.0).
| Value | Result |
|---|---|
| Pressure | 50 PSI |
| Head (feet) | 115.5 ft |
| Head (meters) | 35.2 m |
That means the pump is effectively working against — or capable of lifting water up — a column roughly 115 feet tall, useful context when checking a pump's rated total dynamic head against its pressure-gauge output.
Tips for Working with Head and Pressure
- Static head only. This calculator gives static (standing) head, not accounting for friction losses along pipe runs, which reduce usable pressure at the far end of a system.
- Match your fluid. Always set specific gravity for the actual fluid in the system — using the water default for a denser fluid will overstate head.
- Double-check gauge units. Many gauges display kPa or bar in international markets; picking the wrong unit here silently produces a large error.
- Use head to size pumps. Pump performance curves are almost always plotted against total dynamic head in feet or meters, not PSI.
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Last updated: August 2026 · Reviewed by: Simple Calculator Tools Editorial Team