Pressure Calculator

Calculate pressure from force and area or fluid properties

Pressure from Force and Area

Calculate pressure using the formula: P = F / A

Fluid Pressure

Calculate pressure using the formula: P = ρ × g × h

m/s²

Example Calculations

Explore common pressure calculation scenarios

A car weighs 1500 kg and rests on four tires, each with a contact area of 0.02 m² with the ground.

Force: 1500 kg × 9.81 m/s² = 14715 N (total force)

Force per tire: 14715 N / 4 = 3678.75 N

Pressure: P = F/A = 3678.75 N / 0.02 m² = 183,937.5 Pa (≈ 184 kPa or 26.7 psi)

Calculate the pressure at 10 meters depth in water (density = 1000 kg/m³).

Formula: P = ρ × g × h

Calculation: 1000 kg/m³ × 9.81 m/s² × 10 m = 98,100 Pa (≈ 98.1 kPa or 0.968 atm)

Standard atmospheric pressure at sea level is 101,325 Pa.

Conversions:

  • 1 atmosphere (atm) = 101,325 Pa
  • 1 bar = 100,000 Pa
  • 1 psi ≈ 6,895 Pa
  • 1 torr ≈ 133.322 Pa

So 101,325 Pa = 1 atm = 1.01325 bar ≈ 14.7 psi = 760 torr

Help & Information

Learn about pressure calculations and concepts

Pressure is defined as the force applied perpendicular to the surface of an object per unit area over which that force is distributed.

The SI unit for pressure is the pascal (Pa), equal to one newton per square meter (N/m²).

Pressure is a scalar quantity, meaning it has magnitude but no direction.

1. Pressure from Force and Area:

P = F / A

Where:

  • P = Pressure (Pa)
  • F = Force (N)
  • A = Area (m²)

2. Fluid Pressure:

P = ρ × g × h

Where:

  • P = Pressure (Pa)
  • ρ = Fluid density (kg/m³)
  • g = Acceleration due to gravity (9.81 m/s²)
  • h = Depth of fluid (m)

Absolute Pressure: Measured relative to a perfect vacuum.

Gauge Pressure: Measured relative to atmospheric pressure.

Atmospheric Pressure: Pressure exerted by the weight of the atmosphere (≈101.325 kPa at sea level).

Differential Pressure: Difference between two pressures.

Common pressure unit conversions:

  • 1 Pa = 1 N/m²
  • 1 kPa = 1,000 Pa
  • 1 MPa = 1,000,000 Pa
  • 1 bar = 100,000 Pa
  • 1 atm = 101,325 Pa
  • 1 psi ≈ 6,895 Pa
  • 1 torr ≈ 133.322 Pa