How this calculator works
At rest, a fluid column is supported by a vertical pressure gradient. Integrating for constant density gives a pressure rise proportional to depth. The container shape and total liquid volume do not enter this local relation. The default density is the rounded water value near 4 C; temperature, salinity and compression can change it. This model is unsuitable for a deep gas column with strongly varying density.
Formula
p = p0 + rho g h. Gauge increase = p - p0. Rearrange the equation for the selected unknown; g defaults to standard gravity, 9.80665 m/s2.
Worked example
At 2 m depth in water of density 1000 kg/m3, standard gravity adds 19613.3 Pa. Under a 101325 Pa surface pressure, the result is 120938.3 Pa absolute.
Advertisement
Frequently asked questions
Does a wider tank create more pressure?
At the same fluid density and depth, the local pressure is the same. A larger base can experience a larger total force.
What is gauge pressure?
It is pressure relative to a chosen reference, often local atmospheric pressure. Set surface pressure to zero to calculate the increase alone.
Why can density not be found at zero depth?
At the surface there is no hydrostatic pressure increase, so the measurement contains no information about density.