Pressure Converter
This pressure converter accepts a value in pascals and converts it to PSI, bar, atmospheres, millimeters of mercury, and kilopascals. It is used in tire pressure checks, weather analysis, hydraulic engineering, and medical equipment calibration.
Advertisement
Calculator
See your Pressure Converter results
Enter your email to unlock results — free forever.
No spam, ever. Unsubscribe at any time.
Advertisement
Formula
PSI = Pa ÷ 6894.76
The pascal (Pa) is the SI unit of pressure, equal to one newton per square meter. One PSI (pound-force per square inch) equals 6,894.76 Pa. One bar is 100,000 Pa, one standard atmosphere is 101,325 Pa, and one millimeter of mercury (mmHg) is 133.322 Pa — a historical unit still used in medicine for blood pressure.
How to use the Pressure Converter
- 1
Enter your pressure (pascals)
Enter pressure in pascals to convert to other units.
- 2
Read your results instantly
Results update in real time as you type.
Advertisement
Pressure Units by Application
Different fields use different pressure units based on convention and the magnitudes they typically encounter. Tire pressure and HVAC systems in the US use PSI (pounds per square inch). Industrial and scientific contexts often use bar or kilopascals. Meteorologists use hectopascals (hPa) or millibars for atmospheric pressure. Medical blood pressure readings use millimeters of mercury (mmHg), a unit that dates back to mercury manometers. High-pressure industrial systems sometimes use atmospheres (atm) as a convenient reference to ambient air pressure. Understanding which unit a context uses prevents dangerous misreads.
Practical Pressure Reference Points
Standard atmospheric pressure at sea level is 101,325 Pa (14.696 PSI, 1 atm, 760 mmHg, 1.01325 bar). Typical car tire pressure is 30–35 PSI (207–241 kPa). A bicycle tire runs at 65–130 PSI (450–900 kPa). Normal human blood pressure is about 120/80 mmHg (16/10.7 kPa). Water pressure at the bottom of a 10-meter pool is about 2 atm (29.4 PSI). Deep-sea conditions at 1,000 meters depth reach roughly 100 atm (1,470 PSI). These benchmarks help contextualize pressure readings in any unit.
Tips & Insights
Tire Pressure in PSI vs. Bar
Car tires in the US are labeled in PSI; European vehicles often use bar. A typical tire pressure of 32 PSI equals about 2.2 bar. Keep both conversions in mind when driving internationally or using a foreign-market vehicle.
Blood Pressure in mmHg
Blood pressure is still universally reported in mmHg (Torr), a legacy of mercury sphygmomanometers. A reading of 120/80 mmHg equals 16.0/10.7 kPa. The mmHg unit is retained because medical professionals worldwide are trained on those reference ranges.
Gauge vs. Absolute Pressure
Gauge pressure measures pressure relative to atmospheric pressure, while absolute pressure measures from a perfect vacuum. Tire pressure gauges read gauge pressure — a reading of 0 PSI gauge means the tire is at atmospheric pressure, not flat (though it will feel flat). Add 14.7 PSI to convert gauge pressure to absolute.
Worked Examples
Standard Atmosphere
101,325 Pa (1 standard atmosphere) equals 14.696 PSI, 1.01325 bar, 1 atm, 760 mmHg, and 101.325 kPa.
Car Tire Pressure (32 PSI)
220,632 Pa equals approximately 32 PSI, 2.206 bar, 2.178 atm, 1,655 mmHg, and 220.6 kPa.
Advertisement
Frequently Asked Questions
What is the difference between PSI and bar?
PSI (pounds per square inch) and bar are both pressure units. One bar equals 14.504 PSI. Bar is used in scientific and European industrial contexts; PSI is standard in the US for tires, plumbing, and HVAC.
What is standard atmospheric pressure?
Standard atmospheric pressure is 101,325 Pa, which equals 1 atm, 14.696 PSI, 1.01325 bar, or 760 mmHg. This is the reference pressure at sea level.
Why is blood pressure measured in mmHg?
Blood pressure has historically been measured with mercury manometers, where the reading directly corresponded to how high the mercury column rose. Despite digital sphygmomanometers now being standard, the mmHg unit is retained worldwide for consistency.
How do I convert kPa to PSI?
Divide kilopascals by 6.8948 to get PSI. Alternatively, multiply kPa by 0.14504. For example, 200 kPa ÷ 6.895 = 29.0 PSI.
What is gauge pressure vs. absolute pressure?
Gauge pressure is measured relative to atmospheric pressure (ignoring the atmosphere), while absolute pressure is measured from a perfect vacuum. Most practical gauges read gauge pressure. Add ~101.325 kPa (14.696 PSI) to gauge pressure to get absolute pressure.
Advertisement