Convert pressure units — pascal, PSI, bar, atmosphere, torr, mmHg and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 psi | 0.0689476 mbar | |
| 0.01 psi | 0.689476 mbar | |
| 0.1 psi | 6.89476 mbar | |
| 1 psi | 68.9476 mbar | |
| 5 psi | 344.738 mbar | |
| 10 psi | 689.476 mbar | |
| 50 psi | 3447.38 mbar | |
| 100 psi | 6894.76 mbar | |
| 1000 psi | 68947.6 mbar |
Formula: Millibar = PSI × 68.95
Multiply any psi value by 68.95 to get millibar.
Reverse: PSI = Millibar × 0.0145
Common psi values — factor: 1 psi = 68.95 mbar
| PSI (psi) | Millibar (mbar) | Context |
|---|---|---|
| 0.1 psi | 6.895 mbar | Very low gauge |
| 1 psi | 68.95 mbar | Low tire |
| 5 psi | 344.7 mbar | Bike inner tube low |
| 10 psi | 689.5 mbar | Low hydraulic |
| 14.7 psi | 1,013 mbar | 1 atm |
| 20 psi | 1,379 mbar | Soft tire |
| 30 psi | 2,068 mbar | Car tire low |
| 35 psi | 2,413 mbar | Car tire normal |
| 60 psi | 4,137 mbar | Truck tire |
| 100 psi | 6,895 mbar | Medium hydraulic |
| 150 psi | 1.034e+04 mbar | High hydraulic |
| 1,000 psi | 6.895e+04 mbar | Industrial |
| 3,000 psi | 206,800 mbar | Scuba cylinder |
| 6,000 psi | 413,700 mbar | High-pressure cylinder |
| 1.5e+04 psi | 1,034,000 mbar | Waterjet |
1 psi = 68.95 mbar. Memorize for instant estimates.
Use 68.95 as a quick mental multiplier.
Multiply result by 0.0145 to recover the original psi value.
Inflates and checks car, truck, and bicycle tires to specified psi pressures.
Specifies refrigerant pressures and system test pressures in psi for US equipment.
Designs hydraulic systems rated in psi for American industrial machinery.
Monitors tank pressure (3,000 psi fill) and reserve pressure on US-spec gauges.
Specifies pipe pressure ratings and test pressures in psi for US plumbing codes.
Checks oil pressure (35–65 psi), coolant pressure, and brake line pressure in psi.
PSI (pounds per square inch) is the primary pressure unit in the United States, UK, and other countries using Imperial measures. It equals the force of one pound-force applied over one square inch of area (6,894.76 Pa).
PSI is used for tire pressure (car: 30–35 psi, truck: 80–120 psi), blood pressure measurement in the US, boiler pressure ratings, and hydraulic system specifications in American engineering.
Interesting fact: The deepest ocean dive by a human (Victor Vescovo, 2019, 10,928 m) would have experienced about 15,900 psi of external pressure on the submersible hull.
The millibar (mbar) equals 0.001 bar or 100 pascals, and is numerically identical to the hectopascal (hPa). It became the standard unit for surface pressure in international meteorology in the 20th century.
Weather maps and forecasts worldwide use millibars or hectopascals for surface pressure. Standard sea-level pressure is 1013.25 mbar. Hurricanes and typhoons are characterized by very low central pressures — Hurricane Patricia (2015) reached 872 mbar.
Interesting fact: A 1 mbar pressure difference over 111 km (1° latitude) drives a wind of approximately 1 m/s in mid-latitudes, which is why steep pressure gradients produce strong winds.
Converting psi to millibar is a common task in engineering, medicine, meteorology, and science. Different industries and countries use different pressure units — PSI in the US, bar in Europe, mmHg in medicine, and pascals in physics — making accurate conversion essential for cross-disciplinary work.
Quick reference: 5 psi = 344.7 mbar and 10 psi = 689.5 mbar. For the reverse: 1 mbar = 0.0145 psi. The exact factor is 1 psi = 68.95 mbar.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.