Pressure Converter

Pressure is defined as force per unit area — the amount of force applied perpendicular to a surface divided by the area of that surface. The SI base unit is the Pascal (Pa), equal to one Newton per square meter (N/m²). However, different industries and regions use different pressure units depending on historical convention and practical scale. Engineers in the US commonly use psi (pounds per square inch), meteorologists use hPa or mbar, clinicians use mmHg, and vacuum scientists use Torr. Our pressure converter handles all 15 major pressure units with high-precision conversion factors, making it easy to work across disciplines and international standards.

1. Select Your Units:Choose your source pressure unit from the “From” dropdown and your target unit from the “To” dropdown. Use the swap button (⇄) to instantly reverse the conversion direction. The pressure converter supports 15 units including Pa, kPa, MPa, hPa, bar, mbar, atm, psi, ksi, mmHg, inHg, Torr, inH₂O, mmH₂O, and psf.
2. Enter Your Value: Type the pressure value you want to convert. All conversions use Pascal as the intermediate base unit — your input is first converted to Pa, then from Pa to the target unit, ensuring maximum precision across all unit pairs. Click any reference pressure button to load a real-world example.
3. View Results Instantly: The pressure converter displays your primary result prominently, plus a complete all-units table showing the equivalent value in all 15 pressure units simultaneously — all processed locally in your browser with no data sent to any server.

• 1 atm (standard atmosphere) = 101,325 Pa = 101.325 kPa = 1.01325 bar = 14.696 psi = 760 mmHg = 760 Torr = 29.921 inHg
• 1 bar = 100,000 Pa = 100 kPa = 0.986923 atm = 14.5038 psi = 750.064 mmHg — widely used in European industry as a near-atmosphere reference
• 1 psi = 6,894.757 Pa = 6.895 kPa = 0.06895 bar = 0.06805 atm = 51.715 mmHg — the dominant unit in US engineering and tire pressure
• 1 mmHg ≈ 1 Torr = 133.322 Pa — used in blood pressure (mmHg) and vacuum science (Torr); technically differ by less than 0.000015%

This pressure converter works with absolute pressure — pressure measured relative to a perfect vacuum (zero pressure). In engineering, you may also encounter gauge pressure (pressure relative to atmospheric pressure) and differential pressure (difference between two pressures). To convert gauge pressure to absolute pressure, add 1 atm (101,325 Pa or 14.696 psi). All reference pressures shown in this tool are absolute values. Always verify whether a specification uses gauge (psig, barg) or absolute (psia, bara) pressure before applying conversions.