Pressure units
Each unit in Pa
| Unit | Symbol | In Pa | |
|---|---|---|---|
| pascal | Pa | 1 | exact |
| hectopascal | hPa | 100 | exact |
| kilopascal | kPa | 1000 | exact |
| megapascal | MPa | 1 000 000 | exact |
| bar | bar | 100 000 | exact |
| millibar | mbar | 100 | exact |
| standard atmosphere | atm | 101 325 | exact |
| torr | Torr | 133.322 368 421 | exact |
| millimetre of mercury | mmHg | 133.322 387 415 | exact |
| pound per square inch | psi | 6894.757 293 17 | exact |
| dyne per square centimetre | dyn/cm² | 0.1 | exact |
Conversion matrix
1 unit of the row equals the cell value in the column unit.
| 1 … | Pa | hPa | kPa | MPa | bar | mbar | atm | Torr |
|---|---|---|---|---|---|---|---|---|
| Pa | 1 | 0.01 | 0.001 | 1 × 10−6 | 1 × 10−5 | 0.01 | 9.869 232 667 × 10−6 | 0.007 500 616 827 |
| hPa | 100 | 1 | 0.1 | 1 × 10−4 | 0.001 | 1 | 9.869 232 667 × 10−4 | 0.750 061 6827 |
| kPa | 1000 | 10 | 1 | 0.001 | 0.01 | 10 | 0.009 869 232 667 | 7.500 616 827 |
| MPa | 1 000 000 | 10 000 | 1000 | 1 | 10 | 10 000 | 9.869 232 667 | 7500.616 827 |
| bar | 100 000 | 1000 | 100 | 0.1 | 1 | 1000 | 0.986 923 2667 | 750.061 6827 |
| mbar | 100 | 1 | 0.1 | 1 × 10−4 | 0.001 | 1 | 9.869 232 667 × 10−4 | 0.750 061 6827 |
| atm | 101 325 | 1013.25 | 101.325 | 0.101 325 | 1.013 25 | 1013.25 | 1 | 760 |
| Torr | 133.322 3684 | 1.333 223 684 | 0.133 322 3684 | 1.333 223 684 × 10−4 | 0.001 333 223 684 | 1.333 223 684 | 0.001 315 789 474 | 1 |
Sources: SI Brochure (9th edition, 2019); NIST Special Publication 811 (2008), Appendix B; CODATA 2022 for the bohr, dalton, hartree and rydberg. Factors marked exact follow from the definitions of the units.