Calculate pressure, force, or area using the formula P = F ÷ A.
| Unit | Equal to (Pa) |
|---|---|
| 1 kPa | 1,000 Pa |
| 1 MPa | 1,000,000 Pa |
| 1 bar | 100,000 Pa |
| 1 atm | 101,325 Pa |
| 1 psi | 6,894.76 Pa |
| 1 mmHg | 133.322 Pa |
| 1 inHg | 3,386.39 Pa |
Pressure is defined as the force applied perpendicular to the surface of an object per unit area. It is measured in Pascals (Pa) in the SI system, where 1 Pascal equals 1 Newton per square meter. Pressure is fundamental in physics, engineering, meteorology, and medicine — from tire pressure and blood pressure to atmospheric pressure and hydraulics.
Different fields use different pressure units. Atmospheric scientists use millibars and hectopascals. Engineers often work in psi (pounds per square inch) or bar. Medical professionals measure blood pressure in mmHg (millimeters of mercury). Scientists use Pascals and kilopascals. This calculator supports all major units for convenience.
Standard atmospheric pressure at sea level is 101,325 Pa (1 atm), approximately 1.013 bar, 14.696 psi, or 760 mmHg. This is used as a reference point in many scientific calculations.
Absolute pressure is measured relative to a perfect vacuum. Gauge pressure is measured relative to atmospheric pressure. For example, a car tire inflated to 30 psi gauge has an absolute pressure of about 44.7 psi (30 + 14.7 atm).
As you go deeper in water, more water sits above you, increasing the weight pressing down per unit area. Pressure increases by about 1 atm for every 10 meters of water depth, which is why deep-sea equipment must withstand enormous pressures.