Compute gauge & absolute pressure at any depth using fluid statics. Real‑time diagram, multiple units (Pa, kPa, bar, psi), density presets for water, seawater, mercury & oil. Ideal for divers, hydraulic engineers, and classrooms.
Hydrostatic pressure is the pressure exerted by a fluid at rest due to gravity. Unlike dynamic pressure, it depends only on depth, fluid density, and local gravitational acceleration. The fundamental equation P = ρ g h originates from Blaise Pascal's experiments and remains a pillar of fluid mechanics, civil engineering, and oceanography.
Pgauge = ρ·g·h and Pabs = Patm + ρ·g·h
Where: ρ = fluid density [kg/m³], g = gravitational acceleration [9.80665 m/s² at sea level], h = vertical depth [m]
Our calculator applies the precise formula: Pgauge = ρ × g × h using double-precision arithmetic. Unit conversions follow international standards: 1 Pa = 1 N/m², 1 kPa = 1000 Pa, 1 bar = 100,000 Pa, 1 psi = 6894.75729 Pa. Absolute pressure always includes standard atmospheric pressure (101325 Pa) to avoid confusion. Interactive diagram visualizes the liquid column: a blue fill represents the liquid, a red marker indicates depth, and a green dot shows the pressure evaluation point.
| Depth (m) | Freshwater pressure (kPa) | Seawater pressure (kPa) | Absolute pressure (approx atm) |
|---|---|---|---|
| 1 | 9.81 | 10.06 | 1.099 atm |
| 10 | 98.07 | 100.6 | 1.99 atm |
| 50 | 490.3 | 502.9 | 5.94 atm |
| 100 | 980.7 | 1005.7 | 10.9 atm |
Hoover Dam holds Lake Mead with a maximum depth of about 180 m. At that depth, fresh water (ρ≈1000 kg/m³) creates a gauge pressure ≈ 1.77 MPa (257 psi). The curved arch design transfers the immense force into canyon walls. Using our calculator for 180 m depth shows the enormous force – reinforcing why precise hydrostatic calculations are vital for structural safety.
The Challenger Deep in the Mariana Trench reaches ~11,000 m below sea level. Using seawater density ρ ≈ 1025 kg/m³ and g = 9.8 m/s², the gauge pressure exceeds 110 MPa (~16,000 psi). Our calculator instantly shows at 11,000 m depth: gauge pressure ≈ 110.4 MPa, absolute pressure ≈ 110.5 MPa. This extreme environment crushes most submersibles unless built with reinforced titanium spheres.