Pressure

Calculate pressure from force and area, or convert between different pressure units. Pressure is defined as the normal force per unit area exerted on a surface in a fluid or gas.

Calculator

Inputs

Results

Pressure-- Pa
Pressure-- bar
Pressure-- psi
Pressure-- kPa
UnitConversion Factor (to Pa)Alternative Names
Pascal (Pa)1N/m²
kiloPascal (kPa)1000-
hectoPascal (hPa)100millibar
bar100000-
millibar (mbar)100-
psi (lbf/in²)6894.76-
atmosphere (atm)101325-
mm Hg (Torr)133.322-
inch Hg (inHg)3386.39-
meter H₂O (mH₂O)9806.65-
mm H₂O (mmH₂O)9.80665-
foot H₂O (ftH₂O)2989.07-
Calculator

Inputs

Results

Gauge Pressure-- Pa
Gauge Pressure-- bar
Gauge Pressure-- psi

Pressure Definitions

Absolute Pressure

Absolute pressure (pabs) is measured relative to absolute zero pressure (the pressure at absolute vacuum). All calculations involving gas laws require pressure to be in absolute units.

Gauge Pressure

Gauge pressure (pg) is the pressure difference between a system and the surrounding atmosphere, often measured with a gauge: pg = ps - patm

Standard Atmospheric Pressure

The Standard Atmospheric Pressure at sea-level (273 K / 0°C) is:

  • 1.01325 bar
  • 101,325 Pa (absolute)
  • 14.696 psi
  • 760 mmHg
  • 10.33 mH₂O
  • 29.92 inHg

Standard Pressure Conversion

  • 1 bar = 100,000 Pa = 0.9869 atm = 14.5 psi
  • 1 atmosphere = 101,325 Pa = 760 torr = 14.696 psi = 1.013 bar
  • 1 millibar = 100 Pa = 0.001 bar = 0.750 torr