Convert PSI to and from bar, kPa, atm, Pa, mmHg, and ksi. Useful for automotive, pneumatic, hydraulic, and industrial pressure checks.
This PSI pressure converter handles fast conversion between pounds per square inch and the metric pressure units commonly used in technical work.
PSI is still standard in many US-facing contexts, especially for tires, air compressors, pneumatics, hydraulics, and workshop gauges. At the same time, technical manuals, sensors, and international specifications often use bar, kPa, or MPa instead.
Use the page when you need to move between those systems quickly and want the result displayed in all major pressure units at once. It is especially helpful when a gauge is labeled in psi but the service manual, datasheet, or engineering drawing you are checking is written in bar, kPa, or MPa. Keeping all of the common equivalents visible at once makes it easier to spot whether a reading is in the normal operating range before you adjust a regulator, inflate a tire, or sign off on a pressure test. That extra comparison step helps when the same pressure has to be communicated across US and metric documents.
It is useful whenever a gauge or product label uses PSI but the rest of your specs or calculations use metric units. Seeing bar, kPa, MPa, and atm at the same time reduces conversion mistakes during setup and troubleshooting. That matters most when you are jumping between US-labeled hardware and international reference documents in the same job.
PSI Pressure Converter uses standard pressure conversion factors between Pa, kPa, bar, atm, psi, mmHg, and other units. All conversions are based on the SI definition: 1 Pa = 1 N/m².
Result: See calculator output
Enter any value and select units to see instant conversions across all supported pressure units.
PSI remains common because many gauges, shop tools, and consumer products in the United States are labeled that way. Tire inflation charts, compressor regulators, and hydraulic fittings often use PSI as the primary reference even when the engineering documents behind them are metric.
PSI can be converted through pascals, but in practice most people compare it with bar or kPa because those are easier to read at everyday pressures. A converter is useful when equipment, manuals, and sensors come from different regions and do not share the same unit system.
Automotive tire pressure, air-tool regulators, pneumatic lines, and many household pressure gauges are all typical PSI environments. Converting those readings into kPa or bar helps when you need to compare them with international recommendations or equipment that uses metric labeling.
Common pressure units include psi in US industry, pascals and kilopascals in science, bar in European industry, atmospheres in chemistry, and mmHg in medicine. Which one appears depends mostly on the field and region.
All pressure units can be converted through Pascals as the base unit. For example, to convert psi to bar: first convert psi to Pa (multiply by 6,894.76), then convert Pa to bar (divide by 100,000).
Standard atmospheric pressure is defined as 101,325 Pa = 101.325 kPa = 1.01325 bar = 14.696 psi = 760 mmHg = 1 atm = 29.92 inHg.
Absolute pressure is measured from perfect vacuum (0 Pa). Gauge pressure is measured from atmospheric pressure. Absolute = Gauge + Atmospheric. A tire gauge reading 32 psig means 32 + 14.7 = 46.7 psia.
Different fields developed their own convenient units historically. Medicine uses mmHg (from mercury manometers), US industry uses psi (imperial system), science uses Pa (SI system), and diving uses atm (intuitive for depth calculations).
Atmospheric pressure decreases about 12% per 1,000 meters of altitude gain. Sea level: 101.3 kPa. Denver (1,600m): 83.5 kPa. Mt Everest (8,849m): 33.7 kPa.