Pressure Converter

Convert Pascal, kPa, MPa, Bar, PSI, atm, mmHg, inHg, and more.

Click any card to use that unit as input.

Pascal
Pa
Kilopascal
kPa
Megapascal
MPa
Bar
bar
Millibar
mbar
PSI
psi
Atmosphere
atm
mmHg (Torr)
mmHg
inHg
inHg
Common Reference Pressures
Reference PSI bar kPa mmHg atm
Sea level (standard atmosphere) 14.696 1.01325 101.325 760 1
Car tire (typical) 32 2.206 220.6 1,654 2.18
Blood pressure (systolic, avg) 2.32 0.16 16 120 0.158
Bicycle tire (road) 100 6.89 689.5 5,171 6.8
Scuba tank (full) 3,000 206.8 20,684 155,117 204.1
Deep ocean (1000 m) 1,450 100 10,000 75,006 98.7
Conversion Formulas
Pa 1 Pa = 1 N/m²
kPa 1 kPa = 1,000 Pa
MPa 1 MPa = 1,000,000 Pa
bar 1 bar = 100,000 Pa
mbar 1 mbar = 100 Pa
psi 1 PSI = 6,894.757 Pa
atm 1 atm = 101,325 Pa
mmHg 1 mmHg = 133.322 Pa
inHg 1 inHg = 3,386.389 Pa

Frequently Asked Questions

What is standard atmospheric pressure in all units?

1 standard atmosphere (atm) = 101,325 Pa = 101.325 kPa = 1.01325 bar = 14.696 PSI = 760 mmHg = 29.92 inHg. This is the reference pressure at sea level used in thermodynamics, chemistry, and aviation.

What PSI should my car tyres be inflated to?

Most passenger car tyres are inflated to 30–35 PSI (2.1–2.4 bar / 207–241 kPa). The exact specification is on a sticker inside your driver's door jamb or in the owner's manual — not on the tyre sidewall (that shows the maximum safe pressure, not the recommended pressure).

What is the difference between gauge pressure and absolute pressure?

Absolute pressure is measured relative to a perfect vacuum (0 bar absolute = 0 Pa). Gauge pressure is measured relative to ambient atmospheric pressure. Tyre gauges show gauge pressure — a flat tyre reads 0 PSI gauge but ~14.7 PSI absolute (just the atmosphere). To convert: absolute = gauge + 14.696 PSI (at sea level).

What pressure units are used in medicine and meteorology?

Medicine uses mmHg (millimetres of mercury) for blood pressure — normal is 120/80 mmHg. Meteorology uses millibar (mbar) or hectopascal (hPa) — standard sea-level pressure is 1013.25 hPa. Industrial and engineering applications commonly use bar and PSI.